Preparing a multiple choice test
Python 3, 71
Saved 22 bytes thanks to Ogaday.
Saved 3 bytes thanks to DSM.
Saved a bunch of bytes thanks to an array of bools being valid.
*k,=map(ord,input())
x=65
while x&lt;=max(k):print([v==x for v in k]);x+=1

Takes uppercase command line input.