What is the role of Forwarding Equivalence Class (FEC) in MPLS?

A.
FEC determines how to establish an LSP path.

B.
FEC determines how IP packets are forwarded in MPLS LSP.

C.
None of above.

D.
FEC determines how MPLS labels are stacked in LSP.

E.
FEC determines how a group of IP packets are mapped to an LSP.