>>296816
If it's 50%, then the only possible choice is B. However, if B is the only right choice amongst the four of them, which mean 25% is correct.
If 25% is correct, that means you've got either A or D, two alternatives in four. 2/4 = 2, you've got two possible alternatives, I.E. 50%.
Alternatively, you could say everything is wrong, then that means there's 0% of you getting it right, since there's no alternative after all.
However that means C is correct, because you have 0% chance of getting it right.
If C is correct you have one chance in four, and we're back to 25%.
There are no right choices and you picked a wrong one.