Which of the following best describes Adaptive FRTS?

Which of the following best describes Adaptive FRTS?

A.
Uses BECN frames received to permit input throttling on FR VCs

B.
Uses end to end communication between both routers to throttle bandwidth on a per- VC basis

C.
Uses BECN frames received to permit output throttling on FR VCs

D.
Uses FECN frames received to permit output throttling on FR VCs