The correct option is B BC
In △ABC and △DEF,
∠CAB = ∠FDE (given )
side CA = side FD (given )
∠BCA = ∠DEF (given)
So, by SAS criteria, △ABC ≅△DEF
When two triangles are equal , then its corresponding parts are equal.
Thus, side EF of △DEF corresponds to side BC of △ABC