Psychologists have used four perspectives in their efforts to explain ___. These perspectives include an emphasis on instincts, optimum arousal, a hierarchy of needs, and drive reduction.

Motivation.

Explanation:

Motivation can be simply be explained or defined as what gives someone or Individuals the need or the reason to act in one way or the other. It is some kind of drive that pushes someone to behave or act in a particular manner. Although, in motivation there are more than four perspectives or theories to explain it but the majors perspectives are four and they are; arousal theory( where people act Influence their degree of arousal), instinct theory( where people acts based on their instincts), hierarchy of motives and drive- reduction theory(where people acts in order to reduce tension).

i think it's b or c hope this