1. The encoding standard of typical circuit-switched Private Branch Exchange (PBX) is ___.

A. pulse code modulation (PCM)

B. time division multiplexing (TDM)

C. digital signal (DS) - 1

D. none of the above

2. Which of the following could be an advantage of circuit-switched Private Branch Exchange (PBX), as compared to IP-based and/or packet-based telephony systems?

A. call latency is fixed, minimized, and not affected by other calls.

B. significant proprietary equipment costs.

C. expansion may be expensive for new modules.

D. None of the above