At random has to imply uniform random for the question to make any sense, otherwise you can simply bias your answer choices so the answer is always correct. Gi

At random has to imply uniform random for the question to make any sense, otherwise you can simply bias your answer choices so the answer is always correct. Given uniform random none of the answers is correct: 25%) There's a 50% chance of choosing this answer 50%) There's a 25% change of choosing this answer 60%) There's a 25% chance of choosing this answer If you're allowed to pick your own random distribution then any answer is equally valid. Say we pick one of the 25% answers 25% of the time, and the other ones uniformly: 25%) There's a 25% chance of picking this, as defined by our random distribution. 50%) 37.5% chance 60%) 37.5% chance But if we instead pick our distribution so we pick the 60% answer 60% of the time and the others uniformly we've suddenly got this answer: 25%) ±27% chance 50%) ±13% chance 60%) 60% chance So depending on if you interpret random as "uniform random" or as "whichever random distribution you like" either none of the answers are right or you can pick any answer to be right.