Intermolecular hydrogen bonding is strongest in

Assertion : Boiling point of $p$-nitrophenol is higher than that of $o$-nitrophenol.
Reason : $p$-nitrophenol has intermolecular hydrogen bond whereas $o$-nitrophenol has intramolecular hydrogen bond.

Which of the following has the highest boiling point?

Given below are two statements:
Statement $I$: $o$-Nitrophenol is steam volatile due to intramolecular hydrogen bonding.
Statement $II$: $o$-Nitrophenol has a high melting point due to hydrogen bonding.
In the light of the above statements,choose the most appropriate answer from the options given below:

The intramolecular hydrogen bond is present in

Which of the following has the maximum vapour pressure?