The correct option is C Assertion is incorrect but Reason is correct
A free falling body falls only under the effect of the gravitational force of Earth and hence, any free falling body will have constant acceleration of 9.8 m/s2.
g=GMR2 where G is the constant of gravitation, M is the mass of Earth, and R is the distance between the object and center of earth. This shows that mass of object has no effect on g.