Which two statements about Cisco IOS XR NTP configuration are true? (Choose two.)

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Which two statements about Cisco IOS XR NTP configuration are true? (Choose two.)

A. A network device can obtain NTP time information in three ways: polling the NTP server, listening to NTP broadcasts, and listening to NTP multicasts.
B. NTP authentication supports MD5, SHA1, or SHA2.
C. Client mode is a peer-to-peer mode.
D. The two types of poll-based NTP associations are client mode and symmetric active mode.
E. The Cisco IOS-XR implementation of NTP supports stratum 1 service.
F. In client mode, clients can dynamically learn the NTP sever IP address by listening to the NTP server broadcasts or multicasts.