Which one of these is not compatible with arenes?

In the presence of sunlight,benzene reacts with $Cl_{2}$ to give product $X$. The number of hydrogens in $X$ is $.....$

Which one of the following is used in the preparation of styrene?

What will be the product $A$ in the reaction given below?

Complete the following reactions and identify $A, B, C$ respectively:
$(i)$ $\text{Phenol} + A \xrightarrow{\text{distill}} \text{Benzene}$
(ii) $\text{Benzenesulfonic acid} + B \xrightarrow{150-200^{\circ}C, \text{HCl, high pressure}} \text{Benzene}$
(iii) $\text{Chlorobenzene} \xrightarrow{C, \text{NaOH}} \text{Benzene}$

In the below mentioned compounds,the decreasing order of reactivity towards electrophilic substitution is: