Which Important Contribution to the Study of Motivation Was Made

Which important contribution to the study of motivation was made by Abraham Maslow?

A) Maslow was the first psychologist to study motivation and emotion in nonhuman animals.
B) Maslow's distinction between intrinsic and extrinsic motivation helped psychologists recognize the importance of drives, incentives, and arousal in motivation.
C) Self-actualization is recognized by most motivation researchers as one of the most basic of all human motives.
D) Because of Maslow's influence, greater attention was paid to psychological needs and the motivation and development of people who were psychologically healthy.