Which of the following is a pseudo first order reaction?

AInversion of cane sugar, $C X_{12} H X_{22} O X_{11} + H X_{2} O H X^{+} C X_{6} H X_{12} O X_{6} + C X_{6} H X_{12} O X_{6}$ , in dilute aqueous acid
BDecomposition of $N X_{2} O X_{5}$ in $CCl X_{4}$ solution
CRadioactive decay of $^{14} C$
DDecomposition of gaseous $N X_{2} O X_{4}$ into $NO X_{2}$ at fixed volume

Answer: A

Inversion of cane sugar is truly bimolecular (sucrose and water), but water is in large excess so its concentration is constant, making the reaction pseudo first order. The other processes are unimolecular or genuinely first order, not pseudo first order.

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