Organic compounds can be classified even based upon the function groups. Identify the one which is not a functional group?

About Fundamental Principles of Organic Chemistry

Organic chemistry begins with carbon compounds classified by carbon skeleton, saturation and functional group. Work includes identifying groups such as hydroxyl, carbonyl, carboxyl and amino, applying basic nomenclature, and distinguishing structural, geometric and optical isomers, where the same molecular formula does not necessarily mean the same structure or properties.

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