They are filtered out when the questions are drawn from quizzes, but seemingly not when they are from single questions. If you submit a correction saying it doesn't work in the 50/50 game, an editor can readily amend the answers to read "Both carboxylic acid and amine" and "Neither carboxylic acid nor amine", and it will be clear. A bit clunkier than the simple both/neither, but definitely playable.
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(Editor in Humanities, Religion, Literature and For Children)
That's all, folks!