Concept:Strict functional group classification differentiates aliphatic alcohols from aromatic phenols based on the hybridization of the carbon attached to the hydroxyl group.
Formula:Not applicable to this conceptual question.
Solution:- Options A, B, and D all feature a hydroxyl (-OH) group attached to an \(\text{sp}^3\) hybridized, aliphatic carbon atom. They are valid alcohols.
- Option C (\(\text{C}_6\text{H}_5\text{OH}\)) features an -OH group attached directly to an \(\text{sp}^2\) hybridized aromatic benzene ring.
- This structure forms its own distinct chemical class known as a phenol, possessing vastly different chemical properties (like elevated acidity) compared to aliphatic alcohols.
Why other options are incorrect:A is methanol. B is ethanol. D is benzyl alcohol (the -OH is on the CH2 sidechain, making it an aliphatic alcohol despite the ring).
Quality & Fidelity Assurance:
Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.