I suppose that depends on how pedantic you want to be, cause based on how I read it, you need to "solve" the real answer, which is “c) 0%“, due to the paradoxical situation and then figure out what the chance of picking that correct answer is, if you were to randomly chose one of the 4 options, so either of the 25% options should be correct to mark as a chosen answer and not chosen randomly.

But yes, 25% is not equal to 0%, however English is a lovely language