Which of the following is the Reimer-Tiemann reaction?

In which of the following,ortho/para substitution by an electrophile is very facile?

$I$. $1,2$-dihydroxybenzene
$II$. $1,3$-dihydroxybenzene
$III$. $1,4$-dihydroxybenzene
$IV$. Hydroxybenzene
The increasing order of boiling points of the above-mentioned compounds is:

$A$ 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 $...........$

The major product of the following reaction is:

The increasing order of boiling points of the following compounds is: