$\begin{array}{1 1} \text{(a) o-Nitrophenol is more volatile is steam than those of m and p isomers} \\
\text{(b) o-Nitrophenol shows intramolecular H-bonding } \\ \text{
(c) o-Nitrophenol shows intramolecular H bonding} \\ \text{(d) Melting point of o-Nitrophenol lower than those of m - and -p-isomers}
\end{array} $
