Compared to the Physical Sciences, Like Biology, Chemistry, or Physics

Compared to the physical sciences, like biology, chemistry, or physics, research methods in the social sciences, like criminal justice, sociology or economics, are:

A) easier, because nobody really cares if social scientists get it right or not.
B) more difficult because social concepts are more difficult to measure definitively.
C) easier because social scientists are allowed more leeway in their methodology.
D) about the same in terms of their level of difficulty.