Passage ThreeIn an age when waste today means a lack tomorrow, making use of every available resource becomes more and more important. As coal is being used in greater and greater amounts to produce electricity, larger amounts of ash, by-product of coal,

共用题干
第二篇

Energy and Public Lands

The United States boasts substantial energy resources.Federal lands provide a good deal of US energy
production,the US Department of the Interior manages federal energy leasing（租赁）,both on land and on
the offshore Outer Continental Shelf. Production from these sources amounts to nearly 30 percent of total
annual US energy production.
In 2000,32 percent of US oil,35 percent of natural gas,and 37 percent of coal were produced from
federal lands,representing 20,000 producing oil and gas leases and 135 producing coal leases.Federal lands
are also estimated to contain approximately 68 percent of all undiscovered US oil reserves and 74 percent of
undiscovered natural gas.
Revenues from federal oil,gas,and coal leasing provide significant returns to US taxpayers as well as
State Government.In 1999,for example,$553 million in oil and gas revenues were paid to the US Treasury,
and non-Indian coal leases accounted for over $304 million in revenues,of which 50 percent were paid to
State governments.Public lands also play a critical role in energy delivery.Each year,federal land managers
authorize rights of way for transmission lines,rail systems,pipelines,and other facilities related to energy
production and use.
Alternative energy production from federal lands falls behind conventional energy production,though the
amount is still significant. For example , federal geothermal（地热）resources produce about 7. 5 billion
kilowatt-hours（千瓦时）of electricity per year , 47 percent of all electricity generated from US geothermal
energy.There are 2,960 wind turbines on public lands in California alone,producing electricity for about
300 ,000 people. Federal hydropower（水电）facilities produce about 17 percent of all hydropower produced
in the United States.
Because of the growing US thirst for energy and increasing public unease with dependence on foreign oil
sources,pressure on public lands to meet US energy demand is becoming more intense.Public lands are
available for energy development only after they have been evaluated through the land use planning process.
If development of energy resources conflicts with management or use of other resources,development restric-
tions or impact moderation measures may be enforced,or mineral production may be banned altogether.

Public lands can be used for energy development when_________________.
A:energy development restrictions are effective
B:federal land managers grant permissions
C:they go through the land use planning process
D:there is enough federal budget

共用题干
Electromagnetic Energy

1 White light seems to be a combination of all colors.The energy that comes from a source of light is
not limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy
day it is possible to get a sunburn even though you feel cool.Visible light and the kind of energy that produce
warmth and sunburn are examples of electromagnetic energy.
2 The sun is 93 million miles away from the earth.Yet we can use energy from the sun because elec-
tromagnetic energy travels through space.
3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signals
travel from transmitters to receivers as low-energy electromagnetic waves. Infrared（红外线的）radiation is an
electromagnetic wave.When it is absorbed by matter,heat is produced.Waves of infrared and visible light
have more energy than waves of radio , television , or radar. Ultraviolet rays（紫外线）and X-rays are electro-
magnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating
buildings.Sunlight and electric lights are part of our requirements for normal living. Ultraviolet radiation is
useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel right
through solid objects.They can be used to detect and treat cancer. X-rays are used in industry to find hidden
cracks in metal,and in medicine to reveal broken bones.
4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the
sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is
trapped behind dams and then used to operate electric generators.Other generators are powered by coal,but
the energy stored in coal came from the sun,too.
5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If
the.sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with
electromagnetic radiation led to the theory that mass can be converted into energy.About forty years after the
theory was proposed , nuclear energy was harnessed（利用）by man. Chemical energy comes from electron
（电子）rearrangement. Nuclear energy comes from a change in the nucleus of an atom. Compared with chemi-
cal reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that
the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.
6 Nuclear energy is beginning to compete with coal as an economical source of power to generate elec-
tncity.It is also being used to operate engines in large ships.Scientists continue to seek new and better
methods of obtaining and using energy.

The energy stored in coal_____________.
A:electromagnetic energy
B:electromagnetic energy travels through space
C:came from the sun
D:when a change in the nucleus of an atom takes place
E:when the sunrays are fierce
F:chemical energy is generated

共用题干
Electromagnetic Energy
1 White light seems to be a combination of all colors.The energy that comes from a source of light is not limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kinds of energy that produce warmth and sunburn are examples of electromagnetic energy.
2 The sun is 93 million miles from the earth.Yet we can use energy from the sun because electromagnetic energy travels through space.
3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signals travel from transmitters to receivers as low-energy electromagnetic waves.Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Waves of infrared and visible light have more energy than waves of radio,television,or radar.Ultraviolet rays（紫外线）and X-rays are electromagnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings. Sunlight and electric lights are part of our requirements for normal living.Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel through solid objects. They can be used to detect and treat cancer.X-rays are used in industry to find hidden cracks in metal,and in medicine to reveal broken bones.
4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators.Other generators are powered by coal,but the energy stored in coal came from the sun,too.
5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy.About forty years after the theory was proposed , nuclear energy was harnessed（利用）by man.Chemical energy comes from electron （电子）rearrangement.Nuclear energy comes from a change in the nucleus of an atom.Compared with chemical reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.
6 Nuclear energy is beginning to compete with coal as an economical source of'power to generate electricity.It is also being used to operate engines in large ships.Scientists continue to seek new and better methods of obtaining and using energy.

X-rays and gamma rays can be used to detect and treat cancer______.
A:when it is absorbed by matter
B:when it is cloudy
C:because they can pass through solid objects
D:when the sunrays are fierce.
E:when a change in the nucleus of an atom takes place
F:when electron rearrangement takes place

A growing number of countries want to phase out coal entirely, a transition eased by cheap natural gas and cost of wind and solar power. That is good news. Coal has been the largest engine of change to date, accounting for nearly a third of the rise in average temperatures since the Industrial Revolution. Any pressure on it therefore counts as progress.
Asia accounts for 75% of the world's coal demand. The Chinese goverment has taken steps to limit pollution and support renewables. Yet coal consumption there rose in 2018, as it did the year before. In India coal demand grew by 9% last year. In Vietnam it swelld by altmost a quarter.
To keep the rise in global temperatures to no more than 1.59C relative to pre-industrial times, climatologists insist that almost all coal plants must shut by 2050, which mcans starting to act now.
Today's trends would keep the last coal plant open until 2079, cstimates UBS, a bank. Asia's coal-fired power regiment has a sprightly avcrage age of 15, compared with a creaky 40 years in America, close to retirement.
There are several reasons for this, but one stand out govemment I support. In India state-owned companies invest more than $6bn in coal mining and coal-fired power each year,statebacked banks provide some $10.6bn in financing. Indoncsia doles out more than S2bn annually for consumption of coalfired power. Japan and South Korca finance coal projccts outside their borders.
Govermment support is hardly surprising. State-backed coal firms make money and create jobs. W ind turbines and solar panels provide power only intermittently; for now, dirtier power plants are needed as back up. Gas is pumelling coal in America, but remains a bit-player in India and much of South-East Asia, since it has to be imported and is relatively expensive.
Neverheless, govermments betting on coal face three big risks. One is environmental.
Emissions from coal plants that are already built- -let alone new ones- will ensure that the world exceeds the level of carbon-dioside emissions likely to push global temperatures up by more tham 1.5%C.
There is an cconomio risk, too. Public-sector zeal for coal is matched only by private-sector distaste. Banks, including Asian ones, have increasingly said they will stop funding new coal plants. Wind and solar farms make coal look increasingly expensive. A study has found that private banks provided thre-quarters of loans to Indian renewables projects last year, state-backed banks doled out two-thirds of those for coal.
And then there is politics. Voters do not like breathing soot. More of them are concemed about elimnate change, too, as they face unpredictable growing seasons, foods and droughts.
Which of the followving statements is true?( ).。

A. Govemment support is an important factor for rising coal demand in Asia
B. Japanese govermment does not support coal
C. Solar power is the most used energy in rich countries
D. Gas is playing a bigger role in most Asian countries

共用题干
第二篇

Human and the Earth

In terms of the evolution of life on Earth,human beings have just arrived.Despite their shori time on Earth,however,people have brought about enormous changes to the surface of the planet一changes far out of proportion to the interval of time they have occupied it.
People have more control over their surroundings than any other species on Earth.With the combination of intelligence and manual skill(allowing us to make and use tools),people have found ways to use plant and animal resources,mineral ores,fuels,and many other materials and resources from the Earth.
As the number of people on Earth increases,it becomes increasingly difficult for the population to survive on the resources of the land.The amount of land is limited.Although agricultural production can be increased by use of machinery such as tractors and the addition of fertilizer,the land ultimately can produce only so much food and no more.
As the human population grows,people consume more.Clearly,some locations on Earth already have too many people;in many of these areas,future increases will surely bring about more poverty and suffering. Yet people in rich nations use proportionally far more of the available resources than people in poorer nations.As they consume these resources without restraint,they also waste large amounts of them.
People are only a very small fraction of all the living things on the planet.Yet their numbers create a drain on resources that can't be renewed.For example,the amount of water on Earth is limited,this water is cleaned through natural processes.However,the natural processes for filtering water can clean only a certain amount of water by removing the pollution.Likewise,a limited amount of petroleum can be found under the Earth's surface.Petroleum is a valuable resource.Should people use it up to manufacture petrol for automobiles?As people work to control the planet and make life comfortable,are they using up resources that are needed for their survival?

Who use more available resources according to the passage?
A:Rich people on Earth.
B:Poor people on Earth.
C:People in developed countries.
D:People in developing countries.

共用题干
Energy and Public Lands
The United States boasts substantial energy resources. Federal lands provide a good deal of US energy production,the US Department of the Interior manages federal energy leasing （租赁）both on land and on the offshore Outer Continental Shelf Production from these sources amounts to nearly 30 percent of total annual US energy production.
In 2000,32 percent of US oil,35 percent of natural gas,and 37 percent of coal were pro-duced from federal lands,representing 20,000 producing oil and gas leases and 135 producing coal leases. Federal lands are also estimated to contain approximately 68 percent of all undis-covered US oil reserves and 74 percent of undiscovered natural gas.
Revenues from federal oil,gas,and coal leasing provide significant returns to US taxpayers as well as State Government. In 1999,for example,$553 million in oil and gas revenues were paid to the US Treasury,and non-India coal leases accounted for over$304 million in revenues,of which 50 percent were paid to State governments. Public lands also play a critical role in energy delivery. Each year , federal land managers authorize（许可）rights of way for transmission lines , rail systems , pipe-lines,and other facilities related to energy production and use.
Alternative energy production from federal lands falls behind conventional energy pro-duction , though the amount is still significant. For example , federal geothermal（地热）re-sources produce about 7. 5 billion kilowatt-hours（千瓦时）of electricity per year,47 percent of all electricity generated from US geothermal energy. There are 2,960 wind turbines on public lands in California alone,producing electricity for about 300,000 people. Federal hydropower （水电）facilities produce about 17 percent of all hydropower produced in the United States.
Because of the growing US thirst for energy and increasing public unease with depend-ence on foreign off sources,pressure on public lands to meet US energy demand is becoming more intense. Public lands are available for energy development only after they have been evaluated through the land use planning process.If development of energy resources conflicts with management or use of other resources,development restrictions or impact moderation measures may be enforced,or mineral be banned altogether.

There is a mounting pressure on public lands to satisfy US energy demands because______.
A: many Americans are unhappy with energy development in foreign countries
B: the U. S. is demanding more and more energy
C: quite a few public lands are banned for energy development
D: many Americans think public lands are being abused

共用题干
Electromagnetic Energy
1 White light seems to be a combination of all colors.The energy that comes from a source of light is not limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kinds of energy that produce warmth and sunburn are examples of electromagnetic energy.
2 The sun is 93 million miles from the earth.Yet we can use energy from the sun because electromagnetic energy travels through space.
3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signals travel from transmitters to receivers as low-energy electromagnetic waves.Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Waves of infrared and visible light have more energy than waves of radio,television,or radar.Ultraviolet rays（紫外线）and X-rays are electromagnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings. Sunlight and electric lights are part of our requirements for normal living.Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel through solid objects. They can be used to detect and treat cancer.X-rays are used in industry to find hidden cracks in metal,and in medicine to reveal broken bones.
4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators.Other generators are powered by coal,but the energy stored in coal came from the sun,too.
5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy.About forty years after the theory was proposed , nuclear energy was harnessed（利用）by man.Chemical energy comes from electron （电子）rearrangement.Nuclear energy comes from a change in the nucleus of an atom.Compared with chemical reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.
6 Nuclear energy is beginning to compete with coal as an economical source of'power to generate electricity.It is also being used to operate engines in large ships.Scientists continue to seek new and better methods of obtaining and using energy.

Infrared radiation can produce heat______.
A:when it is absorbed by matter
B:when it is cloudy
C:because they can pass through solid objects
D:when the sunrays are fierce.
E:when a change in the nucleus of an atom takes place
F:when electron rearrangement takes place

共用题干
Electromagnetic Energy
1 White light seems to be a combination of all colors.The energy that comes from a source of light is not limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kinds of energy that produce warmth and sunburn are examples of electromagnetic energy.
2 The sun is 93 million miles from the earth.Yet we can use energy from the sun because electromagnetic energy travels through space.
3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signals travel from transmitters to receivers as low-energy electromagnetic waves.Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Waves of infrared and visible light have more energy than waves of radio,television,or radar.Ultraviolet rays（紫外线）and X-rays are electromagnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings. Sunlight and electric lights are part of our requirements for normal living.Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel through solid objects. They can be used to detect and treat cancer.X-rays are used in industry to find hidden cracks in metal,and in medicine to reveal broken bones.
4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators.Other generators are powered by coal,but the energy stored in coal came from the sun,too.
5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy.About forty years after the theory was proposed , nuclear energy was harnessed（利用）by man.Chemical energy comes from electron （电子）rearrangement.Nuclear energy comes from a change in the nucleus of an atom.Compared with chemical reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.
6 Nuclear energy is beginning to compete with coal as an economical source of'power to generate electricity.It is also being used to operate engines in large ships.Scientists continue to seek new and better methods of obtaining and using energy.

Paragraph 4______
A:Nuclear Reactions as the Lasting Source of the Sun's Energy
B:The Most Important Source of Energy
C:Types of Electromagnetic Energy
D:The Machines Used for Energy Generation
E:Seeking New Sources of Energy
F:The Use of Ultravio1et Radiation in Medicine

共用题干
Electromagnetic Energy
1 White light seems to be a combination of all colors.The energy that comes from a source of light is not limited to the kind of energy you can see.Heat is given off by a flame or an electric light.On a cloudy day it is possible to get a sunburn even though you feel cool.Visible light and the kinds of energy that produce warmth and sunburn are examples of electromagnetic energy.
2 The sun is 93 million miles from the earth.Yet we can use energy from the sun because electromagnetic energy travels through space.
3 Many other kinds of energy are also types of electromagnetic energy.Radio,television,and radar signals travel from transmitters to receivers as low-energy electromagnetic waves.Infrared（红外线的）radiation is an electromagnetic wave.When it is absorbed by matter,heat is produced.Waves of infrared and visible light have more energy than waves of radio,television,or radar.Ultraviolet rays（紫外线）and X-rays are electromagnetic waves with even greater amounts of energy.Infrared radiation is used in cooking food and heating buildings. Sunlight and electric lights are part of our requirements for normal living.Ultraviolet radiation is useful in killing certain disease organisms.X-rays and gamma rays have so much energy that they travel through solid objects. They can be used to detect and treat cancer.X-rays are used in industry to find hidden cracks in metal,and in medicine to reveal broken bones.
4 Usually we use electricity to generate electromagnetic energy.The source of most of our energy is the sun.Heat from the sun causes water to evaporate.When the water falls to the earth as rain,some of it is trapped behind dams and then used to operate electric generators.Other generators are powered by coal,but the energy stored in coal came from the sun,too.
5 Until recently,the source of the tremendous amount of energy given off by the sun was a puzzle.If the sun depended on chemical reactions,it would have used up all its energy long ago.Experiments with electromagnetic radiation led to the theory that mass can be converted into energy.About forty years after the theory was proposed , nuclear energy was harnessed（利用）by man.Chemical energy comes from electron （电子）rearrangement.Nuclear energy comes from a change in the nucleus of an atom.Compared with chemical reactions,nuclear reactions release millions of times more energy per pound of fuel.We now believe that the sun's energy comes from the nuclear reactions in which hydrogen is changed into helium（氦）.
6 Nuclear energy is beginning to compete with coal as an economical source of'power to generate electricity.It is also being used to operate engines in large ships.Scientists continue to seek new and better methods of obtaining and using energy.

Chemical energy is generated______.
A:when it is absorbed by matter
B:when it is cloudy
C:because they can pass through solid objects
D:when the sunrays are fierce.
E:when a change in the nucleus of an atom takes place
F:when electron rearrangement takes place

A growing number of countries want to phase out coal entirely, a transition eased by cheap natural gas and cost of wind and solar power. That is good news. Coal has been the largest engine of change to date, accounting for nearly a third of the rise in average temperatures since the Industrial Revolution. Any pressure on it therefore counts as progress.
Asia accounts for 75% of the world's coal demand. The Chinese goverment has taken steps to limit pollution and support renewables. Yet coal consumption there rose in 2018, as it did the year before. In India coal demand grew by 9% last year. In Vietnam it swelld by altmost a quarter.
To keep the rise in global temperatures to no more than 1.59C relative to pre-industrial times, climatologists insist that almost all coal plants must shut by 2050, which mcans starting to act now.
Today's trends would keep the last coal plant open until 2079, cstimates UBS, a bank. Asia's coal-fired power regiment has a sprightly avcrage age of 15, compared with a creaky 40 years in America, close to retirement.
There are several reasons for this, but one stand out govemment I support. In India state-owned companies invest more than $6bn in coal mining and coal-fired power each year,statebacked banks provide some $10.6bn in financing. Indoncsia doles out more than S2bn annually for consumption of coalfired power. Japan and South Korca finance coal projccts outside their borders.
Govermment support is hardly surprising. State-backed coal firms make money and create jobs. W ind turbines and solar panels provide power only intermittently; for now, dirtier power plants are needed as back up. Gas is pumelling coal in America, but remains a bit-player in India and much of South-East Asia, since it has to be imported and is relatively expensive.
Neverheless, govermments betting on coal face three big risks. One is environmental.
Emissions from coal plants that are already built- -let alone new ones- will ensure that the world exceeds the level of carbon-dioside emissions likely to push global temperatures up by more tham 1.5%C.
There is an cconomio risk, too. Public-sector zeal for coal is matched only by private-sector distaste. Banks, including Asian ones, have increasingly said they will stop funding new coal plants. Wind and solar farms make coal look increasingly expensive. A study has found that private banks provided thre-quarters of loans to Indian renewables projects last year, state-backed banks doled out two-thirds of those for coal.
And then there is politics. Voters do not like breathing soot. More of them are concemed about elimnate change, too, as they face unpredictable growing seasons, foods and droughts.
According to this passage, which energy is the key factor to climate change?( )

A. oil
B. coal
C. gas .
D. solar panels

共用题干
Thirst for Oil
Worldwide every day,we devour the energy equivalent of about 200 million barrels of oil. Most of the energy on Earth comes from the Sun. In fact enough energy from the Sun hits the planet's surface each minute to cover our needs for an entire year,we just need to find an efficient way to use it. So far the energy in oil has been cheaper and easier to get at. But as supplies dwindle,this will change,and we will need to cure our addiction to oil.
Burning wood satisfied most energy needs until the steam-driven industrial revolution,when energy-dense coal became the fuel of choice. Coal is still used,mostly in power sta-tions,to cover one quarter of our energy needs,but its use has been declining since we star-ted pumping up oil. Coal is the least efficient,unhealthiest and most environmentally dama-ging fossil fuel,but could make a comeback,as supplies are still plentiful:its reserves are five times larger than oil's.
Today petroleum,a mineral oil obtained from below the surface of the Earth and used to produce petrol,diesel oil and various other chemical substances,provides around 40% of the world's energy needs,mostly fuelling automobiles. The US consumes a quarter of all oil,and generates a similar proportion of greenhouse gas emissions.
The majority of oil comes from the Middle East,which has half of known reserves. But other significant sources include Russia,North America,Norway,Venezuela and the North Sea. Alaska's Arctic National Wildlife Refuge could be a major new US source,to reduce reliance on foreign imports.
Most experts predict we will exhaust easily accessible reserves within 50 years,though opinions and estimates vary. We could fast reach an energy crisis in the next few decades, when demand exceeds supply. As conventional reserves become more difficult to access,oth-ers such as oil shales and tar sands may be used instead. Petrol could also be obtained from coal.
Since we started using fossil fuels,we have released 400 billion tonnes of carbon,and burning the entire reserves could eventually raise world temperatures by 13℃ .Among other horrors,this would result in the destruction of all rainforests and the melting of all
Arctic ice.

Which of the following statements is NOT meant by the author,according to the second paragraph?
A:Wood was the fuel of choice before coal.
B: The use of coal is declining.
C: Coal is the most environmentally unfriendly fuel next to oil.
D: Coal reserves are plentiful and will be likely to become the major fuel of choice.