what problems would be solved by selecting a moderator to enforce time limit on each student turn to speak during a discussion ?

The correct answer is D. The problem of not all students having a chance to share their opinion.

Explanation

During a discussion, all students must participate and give their opinion or position on a specific topic. However, usually in student groups, some talk for a long time taking time away from other students to intervene. This is a problem in a discussion as it would prevent knowing all the opinions and positions of all the students. Therefore, it would be pertinent to have a person in charge of moderating the time of each student's turn to speak during the discussion. According to the above, the correct answer is D. The problem of not all students having a chance to share their opinion.

for the comment!

b is the answer.   i sat on the lumpy sofa, totally exhausted, with a bad taste in my mouth, wondering what i should do next.