Question: If you choose an answer to this question at random, what is the chance you will be correct?
Answer: When limited to the 4 provided answers, there is no correct answer, because this question is a paradox.
When there is one correct answer, the chance to pick that answer would be 25%. However, the answer 25% exists twice, so there is a 50% chance of picking it. But there is only one answer which says 50% and the chance to pick that answer is 25%.
However, there is no instruction in the question that you need to pick one of the provided answers. My answer could be literally anything, so there is an unlimited number of possible responses. Assuming that there is an unlimited set of incorrect answers but only a limited set of correct answers, the chance of picking a correct answer is 0% which would be my answer.