Contemporary psychology is best defined as the scientific study of

Explanation:

Psychologist realised that the understanding of human behaviour was so complex that they needed to consider it from different points of views: biological, behavioural, cognitive, humanistic, psychodynamic, sociocultural, evolutionary, and bio psychosocial.

So, we can define it as the study of human behaviour considering it as a multidisciplinary subject.

i honestly speaking this is too long

the first question's answer is a.