Points Q, R, and S lie on \(\overline { XZ } \) in such a way that Q is the midpoint of \(\overline { XZ } \), R is the midpoint of \(\overline { XQ } \) and S is the mid point of \(\overline { QZ } \). If QS = 4, what is length of RZ?
(A)8 (B)12 (C)16 (D)20 (E)24
B