what's the correct answer?

The only possible methods for determining if the triangles are congruent is SAS, SSS, ASA, AAS, RHS
So you know what answers you can eliminate.
It tells you CA bisects angle BAD. "Bisect" means cut in half equally, so you know that angle CAB and angle CAD is the same. This is angle proof.
Something seems to be cut off from the picture. Depending on what it tells you (for example line xx = line xx), you can figure out the answer.