On the Cisco IOS XR, which MQC configuration is different than on the Cisco IOS and IOS XE?

A.
On the Cisco IOS XR, WRED can only be applied in the output direction.

B.
On the Cisco IOS XR, marking can only be applied in the input direction.

C.
On the Cisco IOS XR, LLQ can be applied in the input or output direction.

D.
On the Cisco IOS XR, LLQ can use up to four priority queues: level 1, level 2, level 3, and level 4.