Which of the following reactions involves the formation of a carbene intermediate?

Which of the following compounds does not form phenol or phenoxide upon reaction under standard laboratory conditions?

An organic compound $A$ $(C_{6}H_{6}O)$ gives a dark green coloration with ferric chloride. On treatment with $CHCl_{3}$ and $KOH$,followed by acidification,it gives compound $B$. Compound $B$ can also be obtained from compound $C$ on reaction with pyridinium chlorochromate $(PCC)$. Identify $A, B$ and $C$.

The reaction of elemental sulphur with a Grignard reagent followed by acidification leads to the formation of:

Match each of the compounds given in Column $I$ with the reaction$(s)$ that they can undergo,given in Column $II$.
| Column $I$ | Column $II$ |
| :--- | :--- |
| $(A)$ $3-$bromobenzofuran derivative | $(p)$ Nucleophilic substitution |
| $(B)$ Benzyl alcohol | $(q)$ Elimination |
| $(C)$ Salicylaldehyde | $(r)$ Nucleophilic addition |
| $(D)$ $1-$bromo$-2-$nitrobenzene | $(s)$ Esterification with acetic anhydride |
| | $(t)$ Dehydrogenation |

Scheme $1$ and $2$ describe the conversion of $P$ to $Q$ and $R$ to $S$,respectively. Scheme $3$ describes the synthesis of $T$ from $Q$ and $S$. The total number of $Br$ atoms in a molecule of $T$ is. . . . . . . .