Hot conc. ${\mathrm{H}}_2{\mathrm{SO}}_4$ acts as strong oxidising agent which of the following element is oxidised by conc. ${\mathrm{H}}_2{\mathrm{SO}}_4$ into two gaseous products ?

Identify the correct statements from the following.

i) Quartz is a piezoelectric material
ii) All group $14$ tetrachlorides except ${\mathrm{CCl}}_4$ are easily hydrolyzed in water.
iii) The $\mathrm{C}-\mathrm{C}$ bond distance within the layer of graphite is $154\mathrm{pm}$.
iv) ${\mathrm{SiO}}_2$ is soluble in aqueous $\mathrm{HCl}$ solution.

Given below are two statements:
Statement $\mathrm{I}:$ Colourless cupric metaborate is reduced to cuprous metaborate in a luminous flame.

Statement $\mathrm{II}:$ Cuprous metaborate is obtained by heating boric anhydride and copper sulphate in a non-luminous flame.

In the light of the above statements, choose the most appropriate answer from the options given below.

Among the following, the number of halide(s) which is/ are inert to hydrolysis is

(A) ${\mathrm{BF}}_3$
(B) ${\mathrm{SiCl}}_4$
(C) ${\mathrm{PCl}}_5$
(D) ${\mathrm{SF}}_6$