Which of the Following Is a Technique That Works Well

Which of the following is a technique that works well when interviewing subjects about topics that may be emotionally or psychologically challenging?

A) having the researcher ask questions from behind a curtain so that the subject does not see the interviewer
B) asking the subject to respond to questions on a laptop computer
C) putting the researcher in a disguise so that the subject does not know their identity
D) put the subject in a disguise so that they cannot be identified