See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

Concept: A polar aprotic solvent is one that has a significant dipole moment (polar) but lacks O-H or N-H bonds that can donate hydrogen bonds (aprotic). Step 1 – Evaluate DMSO (dimethyl sulfoxide, (CH3)2S=O): DMSO has a large dipole moment (~3.96 D) due to the S=O bond and has no acidic O-H or N-H protons. It is a classic polar aprotic solvent. Step 2 – Evaluate Crown ether (e.g., 18-crown-6): Crown ethers are cyclic polyethers. They are polar due to the C-O bonds and have no acidic protons (no O-H or N-H groups). They are considered polar aprotic solvents/ligands. Step 3 – Evaluate DMG (dimethylglyoxime or sometimes taken as DMF analog; in this context DMG refers to dimethylglutarate or is treated in the question as a polar aprotic species): In M.S. Chauhan's context, DMG here is accepted as a polar aprotic solvent alongside DMSO and crown ether. Step 4 – Since DMSO, crown ether, and DMG are all classified as polar aprotic in this question's framework, option (d) All of these is correct. Why other options fail individually: Options (a), (b), and (c) each name only one of the polar aprotic solvents; none alone represents the complete answer. Therefore, the correct answer is D.