Congruent Factors

I was under the impression that the linguists would only ask questions with two of the congruent factors, and would ask the subjects to indicate what they think the third factor would be. Thus, a question with all three factors would not have been asked during the study, which is why I picked B. Is my mistake in the fact that I am interpreting the question stem wrongly? Is it asking about what kind of answers they sought from the study as a whole? I took it to be asking about what kind of questions did they ask students directly. Is that a wrong interpretation?