Identify the correct option based on the following reaction sequence:
Acetic anhydride $\xrightarrow[(ii) EtOH/H^+/\Delta]{(i) H_3O^+} (A)$ $\xrightarrow[(ii) H_3O^+/\Delta]{(i) NaOEt} (B)$

The major products obtained from the reactions in List-$II$ are the reactants for the named reactions mentioned in List-$I$. Match List-$I$ with List-$II$ and choose the correct option.

List-$I$	List-$II$
$(P)$ Etard reaction	$(1)$ Acetophenone $\xrightarrow{Zn-Hg, HCl}$
$(Q)$ Gattermann reaction	$(2)$ Toluene $\xrightarrow[(ii) SOCl_2]{(i) KMnO_4, KOH}$
$(R)$ Gattermann-Koch reaction	$(3)$ Benzene $\xrightarrow[\text{anhyd. } AlCl_3]{CH_3Cl}$
$(S)$ Rosenmund reduction	$(4)$ Aniline $\xrightarrow[273-278 \ K]{NaNO_2 / HCl}$
	$(5)$ Phenol $\xrightarrow[Zn, \Delta]{ }$

In the following sequence of reactions,a compound $A$ (molecular formula $C_{6}H_{12}O_{2}$) with a straight chain structure gives a $C_{4}$ carboxylic acid. $A$ is :
$A$ $\xrightarrow{LiAlH_{4} / H_{3}O^{+}} B$ $\xrightarrow{\text{Oxidation}} C_{4} \text{ carboxylic acid}$

Arrange the acidity of the given four compounds in decreasing order:
$(I)$ $CH_3COCH_2COCH_3$
$(II)$ $CH_3COCH_3$
$(III)$ $CH \equiv CH$
$(IV)$ $CH_3CHO$
Select the correct answer from the codes given below:

Match the reactant in Column-$I$ with the reaction in Column-$II$:

Column-$I$	Column-$II$
$(i)$ Acetic acid	$(a)$ Stephen
$(ii)$ Sodium phenate	$(b)$ Friedel-Crafts
$(iii)$ Methyl cyanide	$(c)$ $HVZ$
$(iv)$ Toluene	$(d)$ Kolbe's

What are $\underline{A}, \underline{B}, \underline{C}$ in the following reactions?
$(I)$ $(CH_3 CO_2)_2 Ca \stackrel{\Delta}{\longrightarrow} \underline{A}$
$(II)$ $CH_3 CO_2 H \underset{\text{Red P}}{\stackrel{HI}{\longrightarrow}} \underline{B}$
$(III)$ $2 CH_3 CO_2 H \stackrel{P_4 O_{10}}{\longrightarrow} \underline{C}$
$\underline{A} \quad \underline{B} \quad \underline{C}$