$\begin{array}{1 1} \text{(a) (i) Grignard reagent react with water to give corresponding alkynes (ii) $C_6H_5CHClCH_3$ can form a carbocation more easily in $SN$ displacement reaction than $C_6H_5CH_2Cl$}\\ \text{(b) (i) Grignard reagent react with water to give corresponding alkenes (ii) $C_6H_5CHClCH_3$ can form a carbocation more easily in $SN_2$ displacement reaction than $C_6H_5CH_2Cl$}\\ \text{(c) (i) Grignard reagent react with water to give corresponding alkanes (ii) $C_6H_5CHClCH_3$ can form a carbocation more easily in $SN_1$ displacement reaction than $C_6H_5CH_2Cl$}\\(d)\;\text{(d) None of the above}\end{array} $