Assertion : Benzaldehyde is less reactive than ethanal towards nucleophilic attack. Reason : The \(+R\) effect of phenyl group decreases the electron density on the carbon atom of \(>\mathrm{C}=\mathrm{O}\) group in benzaldehyde.

• A

  If both assertion and reason are true and reason is the correct explanation of assertion.
• B

  If both assertion and reason are true but reason is not the correct explanation of assertion.
• Correct answer
  C

  If assertion is true but reason is false.
• D

  If both assertion and reason are false.

Hence, the correct answer is option: 'C'.