AMC 12A 2016 Problem 21

A quadrilateral is inscribed in a circle of radius 200 \sqrt{2}. Three of the sides of this quadrilateral have length 200 . What is the length of its fourth side?

Answer Choices
A. 200
B. 200 \sqrt{2}
C. 200 \sqrt{3}
D. 300 \sqrt{2}
E. 500