Which of the following answers is most true about the BGP Update message?
A.
 It lists a set of path attributes, along with a list of prefixes that use those PAs.
B.
 It lists a prefix/length, plus the PA settings for that prefix.
C.
 It lists withdrawn routes, but never in the same Update message as newly advertised 
routes.
D.
 A single Update message lists at most a single prefix/lengtH.
Explanation:
The BGP Update message lists a set of PAs, plus any prefixes/lengths that use those PAs. It
can also list withdrawn routes in the same Update message as newly advertised routes. It
can also list multiple prefixes in a single Update message.