The relative acidic strengths of benzoic acid, o-toluic acid and p-toluic acid in decreasing order can be given as:

• (A) p-toluic acid > o-toluic acid > benzoic acid
• (B) o-toluic acid > p-toluic acid > benzoic acid
• (C) p-toluic acid > benzoic acid > o-toluic acid
• (D) o-toluic acid > benzoic acid > p-toluic acid

To determine the relative acidic strengths of benzoic acid, o-toluic acid, and p-toluic acid, we need to consider the effects of the methyl group (-CH₃) on the carboxylic acid group (-COOH). The position of the methyl group influences acidity due to its electron-donating effects.

Acidity Influences

In general, electron-donating groups decrease acidity because they destabilize the negative charge on the conjugate base. Here’s how each compound compares:

• Benzoic Acid: No methyl group, serves as a baseline.
• o-Toluic Acid: The methyl group is ortho to the carboxylic acid, which can create steric hindrance but also has some resonance stabilization.
• p-Toluic Acid: The methyl group is para to the carboxylic acid, which allows for resonance stabilization without steric hindrance.

Relative Acidity Order

Considering these factors, the order of acidity from strongest to weakest is:

• p-Toluic Acid
• o-Toluic Acid
• Benzoic Acid

Thus, the correct answer is (C) p-toluic acid > benzoic acid > o-toluic acid.