Long ago, in a galaxy far, far away, a brave group of rebels fought against the evil empire. based on what you have learned about in-group/out-group cognition, you can predict that the rebel fighters are likely to view the defenders of the empire as
a. homogeneous, practically like clones of each other
b. more powerful and more of a threat than they are in reality
c. heterogeneous
d. less competent and more aggressive than they are in reality

a. homogeneous, practically like clones of each other                

Explanation:

          In social psychology and sociology, an in-group is the social group where a person psychologically identifies him as being a member of the same group. Where as in an out-group, individuals do not identify and belongs to the same group.

         In group refers to similar features or homogeneous or belonging to the same group.

         In the context, the rebels finds the defender of the empire or the soldiers of the empire as an in-group, because they belong to the same planet or place. They are like clones to each other and are homogeneous.

Hence the correct option is (a).

a) they had recently endured the tyranny of the british king, parliament, and its royal