Phenol at $25 \, ^\circ C$ is

Which of the following substituted phenols is the strongest acid?

What is the natural source of salicylic acid?

Select the correct decreasing order of acid strength for the following compounds: $(a)$ $Ethanol$ $(b)$ $2-Methylpropan-2-ol$ $(c)$ $Phenol$ $(d)$ $p-Nitrophenol$.

$A + CCl_4 + KOH \to$ Salicylic acid
'$A$' in the above reaction is

The structure of the compound that gives a tribromo derivative on treatment with bromine water is