Which three statements about Cisco HDLC are true? (Choose three.)
A. HDLC serial encapsulation provides asynchronous framing and error detection.
B. Serial link keepalives are maintained by SLARP.
C. HDLC serial encapsulation provides synchronous framing without retransmission.
D. HDLC frame size can be reduced with MPPC compression.
E. The interface is brought down after five ignored keepalives.
F. The interface is brought down after three ignored keepalives.
