What Value of Z (Atomic Number)and a (Mass Number)result in the Following

Multiple Choice

What value of Z (atomic number) and A (mass number) result in the following alpha decay? ${ } _ { 92 } ^ { 238 } U \rightarrow { } _ { z } ^ { A } X + \alpha$

A) Z = 92;A = 238
B) Z = 91;A = 238
C) Z = 90;A = 234
D) Z = 93;A = 238
E) Z = 88;A = 236