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Probability rule
(sh.itjust.works)
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Either A or D but not both. The answer is the letter. It's not a paradox, just undeterminable as written.
... do you perhaps have a 50% chance to get either A or D?
It is a paradox by the rules of the question, but nice try.
You'll also find that most paradoxes can be resolved with more information about how universal laws work btw.