Answer:
(c) Similar by AA~
Explanation:
The outside segments are marked parallel, so the angles formed where the transversals meet them are congruent. That is ∠CBD ≅ ∠EDB, and ∠CED ≅ ∠ECB. (The vertical angles where the lines cross are congruent, as well.)
So, the angles in one triangle are congruent to the angles in the other triangle. The triangles are similar by the AA~ postulate.