A Man Becomes Moderately Aroused Whenever His Wife Wears a Particular

A man becomes moderately aroused whenever his wife wears a particular red outfit. In terms of classical conditioning principles, the red outfit represents a(n) that has become a(n) .

A) unconditioned stimulus; conditioned stimulus
B) unconditioned response; conditioned response
C) previously neutral stimulus; conditioned stimulus
D) conditioned stimulus; unconditioned stimulus