The reaction which involves dichlorocarbene as an electrophile is,

The major products $X$ and $Y$ in the following sequence of transformations are:

Which statement is true?

Explain how the $-OH$ group attached to the carbon of the benzene ring activates the benzene ring for electrophilic substitution reactions.

$A$ trisubstituted compound '$A$',$C_{10}H_{12}O_2$ gives a neutral $FeCl_3$ test positive. Treatment of compound '$A$' with $NaOH$ and $CH_3Br$ gives $C_{11}H_{14}O_2$,with hydroiodic acid $(HI)$ gives methyl iodide,and with hot conc. $NaOH$ gives a compound $B$,$C_{10}H_{12}O_2$. Compound '$A$' also decolorises alkaline $KMnO_4$. The number of $\pi$ bonds present in the compound '$A$' is $...........$

In the reaction $C_6H_5 - X \xleftarrow[HNO_2]{Cu} C_6H_5N_2Cl \xrightarrow[\Delta]{Water} \phi - Y$,what are $X$ and $Y$ respectively?