Planet Z-34 Has a Mass Equal to One-Third That of Earth

Multiple Choice

Planet Z-34 has a mass equal to one-third that of Earth and a radius equal to one-third that of Earth. With g representing, as usual, the acceleration due to gravity at the surface of Earth, the acceleration due to gravity at the surface of Z-34 is

A) g/9 .
B) 3g .
C) g/3 .
D) 6g .
E) 9g .