C should be the answer.
Join BD with a broken line to indicate an imaginary figure ABDE. AD as diagonal, we need both the given statements to prove that t'gle ABD and t'gle ADE are both congruent. Hence, Angles B and E are equal and opposite, so are angles A and D, and sides AB = BD = DE = AE.
Hence, ABDE will be a rhombus, if the given stimulus and statements are true.
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