Which of the following compounds will show the maximum 'enol' content?

Which of the following statements regarding chemical properties of acetophenone are wrong?
$(1)$ It is reduced to methyl phenyl carbinol by sodium and ethanol
$(2)$ It is oxidised to benzoic acid with acidified $KMnO_4$
$(3)$ It does not undergo electrophilic substitution like nitration at meta position
$(4)$ It does not undergo iodoform reaction with iodine and alkali

An organic compound $(A)$ with molecular formula $C_8H_8O$ forms an orange-red precipitate with $2,4-DNP$ reagent and gives a yellow precipitate on heating with iodine in the presence of sodium hydroxide. It neither reduces Tollens' or Fehlings' reagent,nor does it decolourise bromine water or Baeyer's reagent. On drastic oxidation with chromic acid,it gives a carboxylic acid $(B)$ having molecular formula $C_7H_6O_2$. Identify the compounds $(A)$ and $(B)$ and explain the reactions involved.

Iodoform test is not given by

Reductive amination of $A$ forms :
$A$ :

$Propyne$ $\xrightarrow[Hg^{2+} / H_2 O, \Delta]{H^{+}}$ $P$ $\stackrel{Ba(OH)_2}{\rightleftharpoons}$ $Q$ $\xrightarrow{\Delta}$ $R$. $R$ in the above sequence of reactions is: