I've just completed the 57th online multiple choice quiz, that's 570 questions with 3 more to go so that the whole core and AHL is covered. After a while you start to get a bit obsessed with multiple choice and begin to think entirely in terms of 4 choices, the problem is that not everything has 4 choices so you have to make up some stupid ones

Shall I eat that piece of pizza?

A.  Yes
B.  No
C.  Cow
D.  Frog.

However if using multiple choice questions to test knowledge having 2 stupid choices narrows it down to one of two possibles either yes or no which means that a student could get 50% by choosing randomly, that's why question setters have to make up detractors which makes the job that bit more time consuming. I think detractors in questions like the definition of momentum is........are fine, but when the answer is a number I think they are unfair, they lead the student to believe that they have got the right answer when in fact they have made a simple mistake. So I have abandoned numerical detractors which has certainly made my life easier. Maybe I should start a campaign, stop detracting our students.