In the circles above, AD is congruent to WZ. C is the midpoint of AD, B is the midpoint of AC, X is the midpoint of WZ, and Y is the midpoint of XZ. Which of the shaded regions has a larger area?

A. The areas of the two shaded regions are equal
B. The area of the shaded region in circle A is larger
C. The area of the shaded region in circle W is larger
D. It cannot be determined without knowing the lengths of the radi of the circles