When using Frame Relay service interworking, what is true when building a connection?

A.
One side expects Frame Relay frames and the other side expects Frame Relay frames segmented into ATM cells (FR-SSCS).

B.
There is no such thing as Frame Relay service interworking.

C.
Both sides use native Frame Relay.

D.
One side uses native Frame Relay (IETF) and the far side uses native ATM with SNAP or NLPID encapsulation.