Which of the following cannot undergo nucleophilic substitution under ordinary conditions?

Match the reactants in Column-$I$ with their products in Column-$II$.

Column-$I$ (Reactants)	Column-$II$ (Products)
$A$. $H_2C=CH_2 + Br_2 \xrightarrow{CCl_4}$	$i$. $CH_3CH_2CH_2Br$
$B$. $CH_3CH=CH_2 + HI \rightarrow$	$ii$. $BrCH_2-CH_2Br$
$C$. $C_6H_5N_2^+X^- + KI \rightarrow$	$iii$. $CH_3CHICH_3$
$D$. $CH_3CH=CH_2 + HBr \xrightarrow{peroxide}$	$iv$. $C_6H_5I$

Write the structure of the major organic product in each of the following reactions:
$(i)$ $CH_3-CH_2-CH_2-Cl + NaI \xrightarrow[\text{heat}]{\text{acetone}}$
$(ii)$ $CH_3-C(CH_3)_2-Br + KOH \xrightarrow[\text{heat}]{\text{ethanol}}$
$(iii)$ $CH_3-CH(Br)-CH_2-CH_3 + NaOH \xrightarrow{\text{water}}$
$(iv)$ $CH_3-CH_2-Br + KCN \xrightarrow{\text{aq. ethanol}}$
$(v)$ $C_6H_5-ONa + C_2H_5-Cl \longrightarrow$
$(vi)$ $CH_3-CH_2-CH_2-OH + SOCl_2 \longrightarrow$
$(vii)$ $CH_3-CH_2-CH=CH_2 + HBr \xrightarrow{\text{peroxide}}$
$(viii)$ $CH_3-CH=C(CH_3)_2 + HBr \longrightarrow$

$A$ (organic compound) $+ O_2 \to X + Y + Z$. Compound $(A)$ in pure form does not give a precipitate with $AgNO_3$ solution. $A$ mixture containing $70\%$ of $(A)$ and $30\%$ of ether is used as an anaesthetic. Compound $(X)$ and $(Y)$ are oxides while $(Z)$ is a pungent smelling gas. $(X)$ is a neutral oxide which turns cobalt chloride paper pink. Compound $(Y)$ turns lime water milky and produces an acidic solution with water. Compounds $(A), (X), (Y)$ and $(Z)$ respectively will be:

Which of the following products can be obtained from the above reaction?

Chlorination of substance $A$ gives substance $B$. Substance $B$ reacts with alcoholic $KOH$ to give substance $C$,which decolorizes Baeyer's reagent. Ozonolysis of substance $C$ gives $HCHO$. What is substance $A$?