单选题What is a benefit of Internet protocol (IP) telephony?（）A Synchronizes password exchanges for call setupB Creates an encrypted tunnel for voice through a Transmission Control Protocol (TCP)/IP networkC Enables two-way voice transmission over a packet-s
题目
单选题
What is a benefit of Internet protocol (IP) telephony?（）
A
Synchronizes password exchanges for call setup
B
Creates an encrypted tunnel for voice through a Transmission Control Protocol (TCP)/IP network
C
Enables two-way voice transmission over a packet-switched TCP/IP network
D
Eliminates the need for physical cabling in a TCP/IP network