How many of the following reactions yield ${\mathrm{POCl}}_3$?
(i) ${\mathrm{PCl}}_3+{\mathrm{O}}_2\to$ (ii) ${\mathrm{PCl}}_5+{\mathrm{CO}}_2\to$ (iii) ${\mathrm{PCl}}_5+{\mathrm{CH}}_3\mathrm{COOH}\to$
(iv) ${\mathrm{PCl}}_5+{\mathrm{H}}_2\mathrm{O}\to$ (v) ${\mathrm{PCl}}_3+{\mathrm{SO}}_2{\mathrm{Cl}}_2\to$ (vi) ${\mathrm{P}}_4{\mathrm{O}}_{10}+\mathrm{NaCl}\to$
(vii) ${\mathrm{PCl}}_5+{\mathrm{H}}_3{\mathrm{BO}}_3\to$ (viii) ${\mathrm{PCl}}_5+{\mathrm{SO}}_2\to$ (ix) ${\mathrm{PCl}}_3+{\mathrm{SO}}_3\to$

Select the correct option:

${\mathrm{NaBH}}_4+{\mathrm{I}}_2⟶\mathrm{X}\uparrow +\mathrm{Y}\uparrow +2\mathrm{NaI}$

$\mathrm{X}+{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}⟶\mathrm{Y}\uparrow +\mathrm{D}$

$\mathrm{X}+\mathrm{HCl}⟶\mathrm{Y}\uparrow +\mathrm{E}$

$\mathrm{D}$ gives following colour with flame.

${\mathrm{B}}_2{\mathrm{H}}_6+{\mathrm{NH}}_3\frac{\text{ Slowly }}{\text{ Heating }}\times \stackrel{\mathrm{\Delta }}{⟶}\mathrm{Y}+\mathrm{Z}$

Which of the following around $\mathrm{X}$ is correct.

Select the correct option?