Which of the Following Statements About the BFD Asynchronous Mode

Which of the following statements about the BFD asynchronous mode are true? (Choose two.)

A) The local system regularly sends BFD control packets, and the remote system detects the BFD control packets sent from the local system.
B) The local system detects the BFD control packets sent by itself.
C) If one system does not receive any BFD packets from its peer within a detection period, it advertises a session Down event.
D) Each system confirms its connections with other systems in a particular method. After a BFD session is set up, BFD control packets are no longer sent.