thx for replying- and thx becky for the hint but our system is a bit strange it's like:

question: .............

answer1: .........
answer2:.........
answer3:........
answer4:........

and then you can choose:
a: questions 1,2,3 are correct
b: 1 and 3 are correct
c: 2 and 4 correct
d: 4 is correct
e: all are correct

and your have to make 1 cross logically...