Irenaus Eibl-Eibesfeldt (1963)raised Rats in Isolation

Irenaus Eibl-Eibesfeldt (1963) raised rats in isolation.When other rats were finally introduced into their cages,rats raised alone ____, suggesting that ____.

A) could not defend themselves; aggression is learned
B) used the same aggressive behaviors as other rats; aggression need not be learned
C) did not aggress against them; instrumental aggression does not exist in nonhumans
D) fled from the new rats; aggression must be learned