AMC 10B 2009 Problem 9

Segment B D and A E intersect at C, as shown, A B=B C=C D=C E, and \angle A=\dfrac{5}{2} \angle B. What is the degree measure of \angle D ?

Answer Choices
A. 52.5
B. 55
C. 57.5
D. 60
E. 62.5