Which two statements are true about CAC？（）
A. CAC is implemented in the call setup phase to allocate bandwidth resources
B. CAC is implemented in the call maintenance phase to allocate bandwidth resources
CAC is utilized during the call teardown phase to ensure that all resources have been released
D. CAC uses the Cisco RSVP （Resource Reservation Protocol） Agent to integrate call-processing capabilities with the underlying network infrastructure
E. CAC is implemented in the call setup phase to determine the destination of the call
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