Carlos Is a Deeply Introverted Person

Multiple Choice

Carlos is a deeply introverted person.However,at a party with several of his friends he ends up talking more than he normally would.Nevertheless,he still talks less than most of his friends.What is the best explanation of Carlos's behavior in this case?

A) his genetic make-up
B) the situation that he is in
C) his disposition
D) the interaction of the situation and his disposition