Quote from morte
this wouldn't go to the instructor only...but up the chain...do you really want instructors teaching inaccurate information?? And the effort isnt to prove that the OP is smarter than her/his instructor but can provide a cogent argument to correct an error. Tests are teaching tools in and of themselves, and should never have errors such this.
It depends on the specific test question. Instructors can and do make corrections when something is wrong, like say if a question said the normal K+ level is 9-11 mg/dl.
But for the OP's original question, they are probably not going to budge. Taking that particular question up the is only going to waste the student's time.
I brought concerns over test questions to instructors on a few occasions - but only to that instructor and only in private. (I had much better instructors though) I can tell you for sure that a few of the ones I complained about before I learned how to take those tests I sure would not complain about now.