The melting point of $o$-hydroxybenzaldehyde $(A)$ is lower than that of $p$-hydroxybenzaldehyde $(B)$. This is because

The bond angles $\mathrm{H}-\mathrm{O}-\mathrm{N}$ and $\mathrm{O}-\mathrm{N}-\mathrm{O}$ in the planar structure of nitric acid molecule are respectively

The number of lone pairs of electrons on central atom of $\mathrm{ClF}_{3}, \mathrm{NF}_{3}, \mathrm{SF}_{4}, \mathrm{XeF}_{4}$ respectively are

The hybridisation of central atom of $\mathrm{BF}_{3}, \mathrm{SnCl}_{2}, \mathrm{HgCl}_{2}$ respectively is