Which of the following represents the correct order of pK _ a values?

Step-by-step solution

The pK _ a value of an acid is inversely proportional to its acidic strength. A stronger acid has a lower pK _ a value. Let us evaluate the acidic strength of the compounds in option (C): 1. Phenol is a weaker acid than carboxylic acids. 2. Salicylic acid (o-hydroxybenzoic acid) is a stronger acid than benzoic acid due to the stabilization of its conjugate base by intramolecular hydrogen bonding (ortho effect). 3. 2,6-dihydroxybenzoic acid is even stronger because its conjugate base is stabilized by two intramolecu