What are two advantages to using Asynchronous mode instead of Demand mode for BFD?

What are two advantages to using Asynchronous mode instead of Demand mode for BFD? (Choose
two.)

A.
Asynchronous mode requires half as many packets as Demand mode for failure detection.

B.
Asynchronous mode can be used in place of the echo function.

C.
Asynchronous mode supports a larger number of BFD sessions.

D.
Asynchronous mode requires one fourth as many packets as Demand mode for failure detection.

E.
Asynchronous mode’s round-trip jitter is less than that of Demand mode.