Assertion: D-Fructose gives a positive Tollens test. Reason: Fructose is a ketohexose, and ketones are oxidised by Tollens reagent. Choose the correct option.

ABoth assertion and reason are true and the reason explains the assertion.
BBoth are true but the reason does not explain the assertion.
CThe assertion is true and the reason is false.
DThe assertion is false and the reason is true.

Answer: C

Fructose does give a positive Tollens test, but because in the alkaline reagent it isomerises through an enediol to aldoses. Simple ketones are not oxidised by Tollens reagent, so the reason is false.

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