Phone calls have been successful with acceptable audio quality over a WAN link. Recent configuration changes in the WAN routers have resulted in the inability to hear any audio on new calls across the WAN.
Which configuration changes directly cause a loss of audio?
A. a WAN router access list that blocks all UDP ports greater than 10,000
B. a WAN router access list that blocks all UDP ports lesser than 10,000
C. a WAN router access list that blocks all TCP ports greater than 10,000
D. a WAN router access list that blocks all TCP ports lesser than 10,000