Benzaldehyde (C6H5‌CHO) and Ethanal (CH3‌CHO) react in the presence of dilute sodium hydroxide (NaOH) through a reaction known as the Aldol Condensation. This reaction specifically leads to the formation of an α,β-unsaturated aldehyde. The mechanism involves the following steps: 1. Addition Step: Ethanal, in the presence of NaOH , undergoes nucleophilic addition where the enolate ion formed from Ethanal attacks the carbonyl carbon of Benzaldehyde. 2. Formation of Aldol: This results in the formation of 3-hydroxy-3-phenylpropanal as the β hydroxy aldehyde intermediate. 3. Dehydration Step: Heating this intermediate leads to the loss of a water molecule, resulting in the formation of an α,β-unsaturated aldehyde: The balanced chemical equation for the overall reaction can be represented as: C6H5‌CHO+CH3‌CHO‌───────▶‌NaOH‌C6‌H5−CH=CH−CHO+H2O The product formed in this reaction is 3-Phenylprop-2-enal (commonly known as cinnamaldehyde). Therefore, the option B (3-Phenylprop-2-enal & But-2-enal) is the correct answer. Actually, there is no But-2-enal formed; only cinnamaldehyde is produced. Hence, the corrected answer is: Correct Answer: Option B - 3-Phenylprop-2-enal