Answer:
A. The other committee members are unanimous in their opinion.
Step-by-step explanation:
Professor Jones personally disagrees with the other committee members' proposed plan but he would most likely have to vote in favor of their plan if "The other committee members are unanimous in their opinion".
This is because all members of the academic committee are expected to vote, and as usual in the voting system, the opinion with the highest vote is likely to be adopted. If other committee members votes against professor Jones opinion, he would have no other option than to vote in favor of their plan too.
The other Committee members unamimous decision would compel Professor Jones to also Vote in favour of their plan.