In the diagram, the side lengths of four squares are shown. The area of the fifth square is k. What is the value of k?

**Answer Choices**

A. 64

B. 49

C. 36

D. 25

E. 16

In the diagram, the side lengths of four squares are shown. The area of the fifth square is k. What is the value of k?

**Answer Choices**

A. 64

B. 49

C. 36

D. 25

E. 16