Is anyone able to explain why A isnt the correct answer,,can't the first and last sentence serve as support for each other?

I struggled on this one. This is how i explained it to myself --D is the answer because it is incosistent with the principle expressed. Since Yolanda and Mike are both very productive, they should be able to work alone according to Jo's principle. D has them working on the same station, which makes it inconsistent with the principle. In AC A,C,&D, they are mostly unproductive/not the best programmers so they dont have to work alone so it follows that they are either working together or on a single workstation. AC E follows Vanessa's principle. Hope this helps someone that is dazed like i was.

Seems like we all got tricked. i was doing so well getting them right.

#Help is someone able to better explain why A isn't the answer? From my understanding, A is saying that you have to be detached to be objective but B says you dont necessarily have to be detached. Would this not be a point of disagreement for both passage?