The diagram shows joints in motion. Which shows a muscle undergoing eccentric contraction?

[Source: © International Baccalaureate Organization 2020.]

B

The wording of the question was not clear. The intent of this question was for the student to recognize that an eccentric contraction involved a lengthening of the muscle. Also, the student should have recognized that in case C, the hamstrings would normally be relaxing by reciprocal inhibition. However, the question stated that all of the indicated muscles were “contracting.” Thus, both B and C were accepted as correct, making this an “easy” question.