Match the following: The correct answer is

(A) $\mathrm{TiCl}_4(l)+2 \mathrm{Mg}(s) \stackrel{\Delta}{\longrightarrow} \mathrm{Ti}(s)+2 \mathrm{MgCl}_2(s)$ The above reaction is an example of metal displacement reaction in which more reactive metal. (i.e. $\mathrm{Mg}$ ) will displace less reactive metal (i.e. Ti). Thus, option (II) is related with (A). (B) $2 \mathrm{H}_2 \mathrm{O}_2(a q) \longrightarrow 2 \mathrm{H}_2 \mathrm{O}(l)+\mathrm{O}_2(g)$ The above reaction is an example of disproportionation reaction in which $\mathrm{O}$-atom of $\mathrm{H}_2 \mathrm{O}_2$ is oxidised as $\left(\mathrm{O}_2\right)$ and also reduced to $\mathrm{H}_2 \mathrm{O}$. Thus, option (I) is related with (B). (C) $\mathrm{C}(s)+\mathrm{O}_2(g) \stackrel{\Delta}{\longrightarrow} \mathrm{CO}_2(g)$ The above reaction is an example of combination reaction in which carbon(s) combines with $\mathrm{O}_2(g)$ to give $\mathrm{CO}_2(g)$. Thus, option (IV) is related with (C). (D) $2 \mathrm{NaH}(s) \stackrel{\Delta}{\longrightarrow} 2 \mathrm{Na}(s)+\mathrm{H}_2(g)$ The above reaction is an example of decomposition reaction in which $\mathrm{NaH}$ is decomposes to $\mathrm{Na}(s) and \mathrm{H}_2(g)$. Thus, option (III) is related with (D). Hence, $(\mathrm{A}) \rightarrow($\mathrm{II}$),(\mathrm{B}) \rightarrow($\mathrm{I}$),(\mathrm{C}) \rightarrow(\mathrm{IV}),(\mathrm{D}) \rightarrow($\mathrm{III}$)$ and option (a) is the correct answer.