大家看看这两道难题该选什么？

The positive numbers w, x, y,
and z are such that x is 20 percent greater than y, y
is 20 percent greater than z, and w is 20 percent less than x.  What percent greater than z is w
?

A.     15.2%

B.     16.0%

C.     20.0%

D.     23.2%

E.      24.8%