Trapezoid A B C D has parallel sides \overline{A B} of length 33 and \overline{C D} of length 21 . The other two sides are of lengths 10 and 14 . The angles at A and B are acute. What is the length of the shorter diagonal of A B C D ?

**Answer Choices**

A. 10 \sqrt{6}

B. 25

C. 8 \sqrt{10}

D. 18 \sqrt{2}

E. 26