The decreasing order of reactivity of the following compounds towards $Na^{\oplus} O^{\ominus} Me$ is:

The reaction of compound $P$ with $CH_3MgBr$ (excess) in $(C_2H_5)_2O$ followed by addition of $H_2O$ gives $Q$. The compound $Q$ on treatment with $H_2SO_4$ at $0^{\circ}C$ gives $R$. The reaction of $R$ with $CH_3COCl$ in the presence of anhydrous $AlCl_3$ in $CH_2Cl_2$ followed by treatment with $H_2O$ produces compound $S$ [$Et$ in compound $P$ is ethyl group].
$(1)$ The product $S$ is
$(2)$ The reactions,$Q$ to $R$ and $R$ to $S$,are

$A$. Dehydration and Friedel-Crafts acylation	$B$. Aromatic sulfonation and Friedel-Crafts acylation
$C$. Friedel-Crafts alkylation,dehydration and Friedel-Crafts acylation	$D$. Friedel-Crafts alkylation and Friedel-Crafts acylation

Given the answer question $(1)$ and $(2)$

Which one of the following possesses the highest melting point?

Which of the following is most reactive toward nucleophilic aromatic substitution (hydrolysis)?

The reaction between chlorobenzene and chloral in the presence of concentrated sulphuric acid produces

The correct order of reactivity for the reaction involving the cleavage of the $C-X$ bond in the following compounds is: