Consider the following sequence of reactions,

$$ \mathrm{C}_2 \mathrm{H}_4 \xrightarrow[\text { (ii) } \mathrm{Zn} / \mathrm{H}_2 \mathrm{O}]{\text { (i) } \mathrm{O}_3} P \xrightarrow[\text { (ii) } \mathrm{H}_2 \mathrm{O} / \mathrm{H}^{+}]{\text {(i) } \mathrm{CH}_3 \mathrm{MgBr} / \text { Ether }} Q \xrightarrow[\mathrm{CH}_2 \mathrm{Cl}_2]{\mathrm{PCC}} R $$

The incorrect statement about $R$ is

Arrange the following in the correct order of their reactivity towards nucleophilic addition reactions.

$$ \text { What is } B \text { in the given reaction? } $$

$$ \text { What is } X \text { in the following reaction sequence? } $$