The correct answer is ∠1≅∠3 by the transitive property of congruence 
How to Prove this Problem?
Given ABCD is parallelogram and DC bisects ∠BDE
To prove ∠1≅∠3
- It is given that ABCD is a parallelogram and So, AB is parallel DC by the definition of parallelogram so ∠1≅∠2 by alternate interior angle theorem 
It is also given DC bisects ∠BDE
So, ∠2≅∠3 by definition of angle bisector 
Therefore ∠1≅∠3 by the transitive property of congruence 
Hence it is proved 
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