What Type of Experience Did Freud Have That Influenced His

What type of experience did Freud have that influenced his theory of personality?

A) B.F. Skinner convinced him to look at the unconscious conflicts that shape behaviour.
B) Many of his clients' problems stemmed from physical causes.
C) He spent time in WWI where he witnessed great suffering.
D) He found that some of his patients' symptoms had no observable physical or neurological causes.