To conclude your proof, the appropriate statement to place at the end is:
"Finally, corresponding parts of congruent triangles are congruent by the CPCTC Theorem, so ∠A ≅ ∠C."
This statement aligns with the conclusion drawn from the congruence of triangles \(△ABD\) and \(△CBD\) established through the SAS Congruence Theorem. The Base Angles Theorem states that in an isosceles triangle, the angles opposite the equal sides are also equal. Thus, since you have established that the triangles are congruent, the angles \(∠A\) and \(∠C\) must be congruent as well.