Hydrolysis of an ester gives a carboxylic acid which on Kolbe's electrolysis yields ethane. The ester is

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 following compounds in increasing order of their property as indicated:
$(i)$ Acetaldehyde,Acetone,Di-tert-butyl ketone,Methyl tert-butyl ketone (reactivity towards $HCN$)
$(ii)$ $CH_3CH_2CH(Br)COOH$,$CH_3CH(Br)CH_2COOH$,$(CH_3)_2CHCOOH$,$CH_3CH_2CH_2COOH$ (acid strength)
$(iii)$ Benzoic acid,$4$-Nitrobenzoic acid,$3,4$-Dinitrobenzoic acid,$4$-Methoxybenzoic acid (acid strength)

Select the $CORRECT$ increasing order of boiling points of alcohols,amines,and carboxylic acids of comparable molar mass from the following.

With reference to the scheme given,which of the given statement$(s)$ about $T$,$U$,$V$ and $W$ is (are) correct?
$A$. $T$ is soluble in hot aqueous $NaOH$
$B$. $U$ is optically active
$C$. Molecular formula of $W$ is $C_{10}H_{18}O_4$
$D$. $V$ gives effervescence on treatment with aqueous $NaHCO_3$

$CH_3-C(=O)-OH$ $\xrightarrow{NaH^{14}CO_3} (A) (\text{gas})$ $\xrightarrow[(ii) H_3O^{+}]{(i) PhMgBr} (B)$
$CH_3-S(=O)_2-OH$ $\xrightarrow{NaH^{14}CO_3} (C) (\text{gas})$ $\xrightarrow[(ii) H_3O^{+}]{(i) PhMgBr} (D)$
Product $(B)$ and $(D)$ in the above reaction are: