2 comments
Solving this problem is easy, if A or D were correct, P = 0.5, if C or B were correct P = 0.25, since A and D require P = 0.25, and since C and B require P = 0 or 0.5 respectively, there is no correct solution that can be given, therefore the solution is "Undefined".
Anyway, have a good troll!
It's easier than that. It's 50/50, you're either right or you're not :p