The reactants $(A)$ and $(B)$ are:

Compound $P$ $(C_{8}H_{8}O)$ gives a red-orange precipitate with $2,4-DNP$ reagent and it does not reduce Fehling's reagent. On drastic oxidation with chromic acid, $P$ gives an aromatic product $Q$ that produces effervescence on treating with aqueous $NaHCO_{3}$. Compound $P$ and $Q$, respectively, are:

If the enolate ion combines with the carbonyl group of an ester,we get:

The major product of the following reaction sequence is

Considering the following reaction sequence,the correct statement$(s)$ is(are):
$A$. Compounds $P$ and $Q$ are carboxylic acids.
$B$. Compound $S$ decolorizes bromine water.
$C$. Compounds $P$ and $S$ react with hydroxylamine to give the corresponding oximes.
$D$. Compound $R$ reacts with dialkylcadmium to give the corresponding tertiary alcohol.

Primary aldehyde on oxidation gives