I would say the chief reason a person becomes a supervisor is C) work-related knowledge. Because a person might have A, B, and D, and still not want to be a supervisor.
I think the correct answer is C i got i right on my test
in that paragraph, the expression Mounting evidence could be a bit confusing, but it indicates that there's been reaserch about it before, and that it all points in the same direction, the more research proving the same point means the data is convincing. The answer is D.
