Multiple Choice Question

A panel meets every six months to discuss their answers to assigned questions. Bill, Ted, Mark, and Jim are members of the panel. Which of the following could threaten the effectiveness of the panel?
A.

Mark can't make it to the meetings and has to contribute by telephone.
B.

Jim gets mad at the rest of the panel, turns in his diary, and quits the panel.
C.

None of the panel members know each other outside of the study.
D.

The panel members are all different ages.

B. Jim gets mad at the rest of the panel, turns in his diary, and quits the panel.