单选题The responsibility of the police force of Public Transit is to _____.A enhance public securityB build a free transit systemC control the number of ridersD ensure a convenient transit system

It can be inferred that the term “public duty” (pra.2), in the context of the passage, means which of the following?

The use of （）in many ways reduces staffing needs, minimizes in transit damage and theft, shorten time in transit because of reduced port turnaround time.

Passage 1Rapid Police Response　　A  Police departments in the United States and Canada see it as central to their role that they respond to calls for help as quickly as possible. This ability to react fast has been greatly improved with the aid of technology. The telephone and police radio, already long in use, assist greatly in the reduction of police response time. In more recent times there has been the introduction of the “911” emergency system, which allows the public easier and faster contact with police, and the use of police computer systems, which assist police in planning patrols and assigning emergency requests to the police officers nearest to the scene of the emergency.　　B  An important part of police strategy, rapid police response is seen by police officers and the public alike as offering tremendous benefits. The more obvious ones are the ability of police to apply first-aid lifesaving techniques quickly and the greater likelihood of arresting people who may have participated in a crime. It aids in identifying those who witnessed an emergency or crime, as well as in collecting evidence. The overall reputation of a police department, too, is enhanced if rapid response is consistent, and this in itself promotes the prevention of crime. Needless to say, rapid response offers the public some degree of satisfaction in its police force.　　C  While these may be the desired consequences of rapid police response, actual research has not shown it to be so beneficial. For example, it has been demonstrated that rapid response leads to a greater likelihood of arrest only if responses are in the order of 1-2 minutes after a call is received by the police. When response times increase to 3-4 minutes-still quite a rapid response-the likelihood of an arrest is substantially reduced. Similarly, in identifying witnesses to emergencies or crimes, police are far more likely to be successful if they arrive at the scene no more than four minutes on average, after receiving a call for help. Yet both police officers and the public define “rapid response” as responding up to 10-12 minutes after calling the police for help.　　D  Should police assume all the responsibility for ensuring a rapid response? Studies have shown that people tend to delay after an incident occurs before contacting the police. A crime victim may be injured and thus unable to call for help, for example, or no telephone may be available at the scene of the incident. Often, however, there is no such physical barrier to calling the police. Indeed, it is very common for crime victims to call their parents, their minister, or even their insurance company first. When the police are finally called in such cases the effectiveness of even the most rapid of responses is greatly diminished.　　E  The effectiveness of rapid response also needs to be seen in light of the nature of the crime. For example, when someone rings the police after discovering their television set has been stolen from their home, there is little point, in terms of identifying those responsible for the crime, in ensuring a very rapid response. It is common in such burglary or theft cases that the victim discovers the crime hours, days, even weeks after it has occurred. When the victim is directly involved in the crime, however, as in the case of a robbery, rapid response, provided the victim was quickly able to contact the police, is more likely to be advantageous. Based on statistics comparing crimes that are discovered and those in which the victim is directly involved, Spelman and Brown (1981) suggest that three in four calls to police need not be met with rapid response.　　F  It becomes clear that the importance of response time in collecting evidence or catching criminals after a crime must be weighed against a variety of factors. Yet because police department officials assume the public strongly demands rapid response, they believe that every call to the police should be met with it. Studies have shown, however, that while the public wants quick response, more important is the information given by the police to the person asking for help. If a caller is told the police will arrive in five minutes but in fact it takes ten minutes or more. Waiting the extra time can be extremely frustrating. But if a caller is told he or she will have to wait 10 minutes and the police indeed arrive within that time, the caller is normally satisfied. Thus, rather than emphasizing rapid response, the focus of energies should be on establishing realistic expectations in the caller and making every attempt to meet them.List of Headings　　i　　　　The presumptions of policy makers　　ii　　　　Need for more equitable parenting policies　　iii　　　 The impact of dual employment　　iv　　　 Comparison of employed and non-employed mothers　　v　　　　The benefits of balanced responsibility　　vi　　　 The unchanged role of the female parent　　vii　　　The effect of stress on the female parent　　viii　　　Disadvantages of parental equality　　ix　　　 The experts’ view of the male parent’s role　　x　　　　Commitment of mothers to their paid jobs　　xi　　　 Origins of anxiety in working mothers　　Example　　　　　　Answer　　Section A.　　　　　　…ii…　　1. Section B　　2. Section C　　3. Section D　　4. Section E　　5. Section F

The purpose of installing a camera inside the new buses is to _____.

Two figures are mentioned in the last paragraph to indicate _____.

The responsibility of the police force of Public Transit is to _____.

The best title for the passage might be_____.