Hardest multiple choice question ever

This is an old one that makes the rounds from time to time.

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[random-uploaders]

this is the most useless useful question ever

[greenmarble]

'When the only winning move is not to play'

[WattSCar]

I understand it's a paradox. But, as a test maker, you dont put 2 same answers/values in a multiple choice. So if it happens, pick the letter in which the answer first appears. So letter A = 25%.

[matthewharrigan]

"this question" is undefined. Therefore the correct answer is undefined. Undefined is not one of the enumerated choices. Therefore there is a 0% chance of randomly picking undefined.

[YoungGandalf]

I feel like this is how voting in a political election works. No matter who you choose, it's wrong.

[alfiehiggins]

An even more intersting one would be the same question with answers A)25%, B)75%, C)75%, D)75% because if A is correct then only 1 option out of the 4 would say 25% which is true, but if B, C or D is correct then exactly 3 of the 4 options would say 75% which is also true so all 4 options must be valid, but if all 4 options are correct then the chances of getting the correct answer would be 100% but no answers say 100% so there are actually no correct answers. How interesting!

[trevorbradley]

"You will be correct" and "Your answer will be correct" are different things.

[haromaticc]

The answer is b. 50%. If you are choosing in random and there are two same options, you have 50 % chance of getting it right. If you choose 25 % ie either a or d then you would get 50% as the right answer. Remember that the question asks for the percentage of the option a, b, c, or d and not the value of each option. Now lets think more and if we read the question, we will find that it asks for probability of the correct answer. Hence at random you will have 25 percent of getting it right. Since one of the options is 0%, we make an educated guessand conclude it most definitely is false. Hence now our range of guessing is limited to options a, b, and d which makes it a 33.333% of getting it right. Since two options are the same, we are limited to 2 options b and either of options a or d. Hence the probability increases to 50%. Hence the correct option is option b. 50%.

[earthbind]

Nice! So no matter which answer you choose, you will be incorrect, even if you pick 0%.
Well, since the correct answer changes with your chosen answer, I guess the actual correct answer is
"If you choose A) or D) then it's B), but if you choose B) or C) then it's A)."

[_mara_]

You just need to get a little less random, but not completely. Imagine you select a random option, but giving different probabilities to each one. If you make the sum of the probabilities of selecting A or D to be 25% then 25% would be the correct answer.

[chrisg]

Delicious! Years ago I came up with a question version of the Liar paradox "This statement is false" (which if true is false and if false, true). It's "What is the incorrect answer to this question?" A correct answer is incorrect and vice versa. Sort of applies to the example in the vid.

[the-boy-who-lived]

So in short, there is 0% chance I'm getting that correct as no answer is correct. So now teacher has to face a paradox if I said 0%. In that way I used the Uno reverse

[asifhossainafridi]

The answer is if you choose option A or D, your chance to be correct is 50%
If you choose option B or C your chance to be correct is 25%.

[-radioactivity]

Actually the answer is 0% because 0% is actually 33.33% in reality. Letting 25% options to be one option and 50% to be other, [seeing A, B, C only not the options], the total cases will be 3 so the probability will be 33.33% which was actually of C which was 0%.

[aaronbredon]

This is an example of Russel's Paradox, and any true answer must be made in a mathematics that deals with self referential statements. I will use meta levels for this answer. Another valid answer is to state that the question is badly formed as self referential statements cannot exist.
The self referential nature makes this a meta question, which needs to be answered in a higher meta level than meta⁰.
All 4 of the multiple choice answers are meta⁰ answers, and are thus incorrect. The correct answer is (meta¹ 0%), not C (meta⁰ 0%)
If this is a scantron question, the answer is most likely E, as that would mean "other".
If this is a written test, then answer meta¹ 0%.

[kannychow]

"How about a nice game of chess?" 😄

[daltonzoletta]

The answer is not important, the journey to discover the answer, is.

[amoghverma]

Not playing a game is also winning the game. This is what also life teaches us sometimes.

Let's not always try to be Jack of all

[vinwonsenobi]

the only winning move is to actually follow the directions and choose randomly.

[IMakeMetal]

The question says choose an answer at random but it doesn't require you to choose uniformly at random. I can assign a probability of choosing each answer equal to their representative values and then it'll be correct.