The Stipulation of the PhD as the Credential Required to Practice

The stipulation of the PhD as the credential required to practice clinical psychology came about

A) as a way for universities to cash in on the increasing number of students applying to graduate school.
B) as an attempt on the part of psychologists to compete academically with psychiatrists.
C) because of the fear that people would practice psychology without proper training and accreditation.
D) because the field of Psychology had grown so much that more training was required to cover all of the information that had been gathered.