A Researcher Plans to Conduct Interviews with the First Four

A researcher plans to conduct interviews with the first four participants in a qualitative study, and then the researcher plans to have an assistant conduct several interviews, for the remainder of the interviews. The first thing the researcher does with the research participants is to perform a pilot interview on one participant and to have the assistant conduct a pilot interview on a different participant, and then they compare notes, discussing the process. Why is this a good idea?

A) This establishes interrater reliability.
B) Their styles may differ, and this way they can imitate one another's styles.
C) Pretesting of the interview protocol is essential.
D) They can begin the process of data analysis at once.