Which of the following is a trihydric phenol?

$A$ compound $A$ $(C_{7}H_{8}O)$ is insoluble in $NaHCO_{3}$ solution but dissolves in $NaOH$ and gives a characteristic colour with neutral $FeCl_{3}$ solution. When treated with bromine water,compound $A$ forms the compound $B$ with the formula $C_{7}H_{5}OBr_{3}$. $A$ is:

Write the reactions of phenol with: $(i)$ $CH_3COCl$,$(ii)$ $(CH_3CO)_2O$,$(iii)$ $NaOH$,$(iv)$ chromic acid,and $(v)$ heating with zinc dust.

Which of the following compounds will be the most acidic?

Which of the following is a pair of dihydric phenols?

The main product of the following reaction will be: