The correct option is A - Opening. In general, the main idea of a text (independently of its format) is stated in the begining of it. In this case, the purpose or main reason (idea) should be indicated in the beggining so that in the body, that purpose can be further developed in detail (with main points and ideas behind the interview). Finally, in the closing, it could be pointed out once again the purpose of the interview and its main points and also it could be added further information such as a reflexion or further considerations as regards of the interview.
