Insel and Colleagues (1988) Conducted a Study in Which Rhesus

Insel and colleagues (1988) conducted a study in which rhesus monkeys were raised either with a sense of control or without a sense of control, and they were later exposed to an anxiety-inducing drug.What did the researchers conclude?

A) Chemicals such as neurotransmitters influence behaviour in different ways depending upon the psychological history of the individual.
B) Chemicals such as neurotransmitters may have little or no effect on behaviours related to anxiety.
C) Chemicals such as neurotransmitters have only indirect effects on behaviour.
D) Chemicals such as neurotransmitters have few reliable and consistent effects on observed behaviour.