Thanks for the question! We’re asked here to find an answer choice that weakens (or counters) Dr. Ruiz’s argument. Dr. Ruiz’s argument concerns the relationship between the bias of panel members and coming to conclusions. (C), however, does not mention this, and so it neither strengthens nor weakens the argument—it is just irrelevant. (C) concerns how lively the discussions are, as opposed to what Dr. Ruiz’s argument concerns, and so it’s wrong. Hope this helps! Feel free to ask any other questions that you might have.
