Which One of the Following Is Considered to Be a Reason

Which one of the following is considered to be a reason for the development of the biopsychosocial model of health and the area of health psychology in general?

A) Social factors are more important than biological factors in affecting health
B) The leading causes of death today are largely preventable
C) How and what one thinks is the sole determinant of one's state of bodily health
D) One cannot separate organisms from their physiology and from their social setting