This question already has an answer here:
I stumbled over a probability paradox on the internet:
If you choose an answer to this question at random, what is the chance that you will be correct?
Given that "at random" means choosing each option with equal probability, each option had a chance of 25% to be correct. But since there are 2 options with 25% as the solution, we get 50% of being correct. In this case, B) would be correct. But then again, the probability of choosing B) at random would be 25%. And so on.
Does this paradox have a name? Is there something I can read on it?