Of the choices that you have given us here, C is the best answer.
First of all, you should note that D cannot possibly be the correct answer. This is because two of the options that you are given here (A and C) cannot both be true. If Khrushchev treated Kennedy “badly and disrespectfully,” he could not possible have “treated him with respect.” Therefore, D cannot possibly be the answer and you should rule that option out.
Historians typically say that C is the correct answer. Kennedy was very young and was in his first few months as president. Khrushchev felt that he would be able to bully Kennedy because of these factors. Kennedy did feel that Khrushchev had gotten the better of him during the talks. The fact that the Soviet leader was able to push Kennedy around shows that C is the best answer.