Assertion: P- Hydroxybenzoic acid has a lower boiling point than o- hydroxybenzoic acid. Reason: O- Hydroxybenzoic acid has intramolecular hydrogen bonding. A. Both assertion and reason are true and reason is the correct explanation of assertion. B. Both assertion and reason are true and reason is not the correct explanation of assertion. C. Assertion is true and reason is false. D. Assertion is false and reason is true.

The correct answer is B. Both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.

Explanation:
P-Hydroxybenzoic acid has a lower boiling point than o-hydroxybenzoic acid due to the difference in the intermolecular hydrogen bonding between the molecules. While o-hydroxybenzoic acid can form intramolecular hydrogen bonding due to the proximity of the hydroxyl group and the carboxylic acid group within the same molecule, this does not significantly affect its boiling point compared to p-hydroxybenzoic acid, which lacks this intramolecular hydrogen bonding but can still form intermolecular hydrogen bonds with neighboring molecules. The primary factor influencing the boiling point in this case is the strength and number of intermolecular forces, not intramolecular hydrogen bonding. Therefore, while both statements are true, the reason provided does not correctly explain why p-hydroxybenzoic acid has a lower boiling point.