Evidence from studies of mental rotation tasks indicates that subjects take longer to make judgments about objects if the objects must be rotated further in order to match the standard. What does this finding suggest?

a) People are actually going through the process of rotating in their minds
b) People need to hold the object in order to mentally rotate it.
c) People have difficulty mentally manipulating objects that are rotated.
d) People can mentally rotate objects faster if they are familiar.

A