NOTES上有个问题不太懂，请教一下各位高手

Which of the following statements is least likely correct? A member or candidate:

A. can participate or assist in a violation simply by having knowledge of the violation and not taking action to stop it

B. is held responsible for participating in illegal acts in instances where violation of the law is evident to those who know or should know the law

C.must report evidence of lefal violation to the appropriate governmental or regulatory organization

答案是选C，可是我觉得A错得很明显，麻烦各位指点一下，谢谢！

出自：NOTES BOOK 1 page 76