The major product of the following reaction is:

Which of the following can decolorize aldehydes and ketones?

Product $(D)$ in the above sequence is:

Match the reactions in Column $I$ with appropriate options in Column $II$.

Column $I$	Column $II$
$A$. $Ph-N_2Cl + Ph-OH \xrightarrow{NaOH/H_2O, 0^{\circ}C} Ph-N=N-Ph-OH$	$p$. Racemic mixture
$B$. $Pinacol \xrightarrow{H_2SO_4} Pinacolone$	$q$. Addition reaction
$C$. $Ph-CO-CH_3 \xrightarrow{1. LiAlH_4, 2. H_3O^+} Ph-CH(OH)-CH_3$	$r$. Substitution reaction
$D$. $4-chlorocyclohexanethiol \xrightarrow{Base} Thiacycloheptane$	$s$. Coupling reaction
	$t$. Carbocation intermediate

Geminal diols (compounds with two $-OH$ groups on the same carbon atom) are generally unstable. However,which of the following is stable?

An organic compound $P$ having molecular formula $C_6H_6O_3$ gives a ferric chloride test and does not have an intramolecular hydrogen bond. The compound $P$ reacts with $3$ equivalents of $NH_2OH$ to produce oxime $Q$. Treatment of $P$ with excess methyl iodide in the presence of $KOH$ produces compound $R$ as the major product. Reaction of $R$ with excess iso-butylmagnesium bromide followed by treatment with $H_3O^{+}$ gives compound $S$ as the major product. The total number of methyl $(-CH_3)$ groups in compound $S$ is . . . .