Acetone on addition to methyl magnesium bromide forms a complex,which on decomposition with acid gives $X$ and $Mg(OH)Br$. Which one of the following is $X$?

Which of the following pairs is differentiated by the iodoform test?

Columns $1$,$2$,and $3$ contain starting materials,reaction conditions,and type of reactions,respectively.

$Column-1$	$Column-2$	$Column-3$
$(I)$ Toluene	$(i)$ $NaOH / Br_2$	$(P)$ Condensation
$(II)$ Acetophenone	$(ii)$ $Br_2 / h\nu$	$(Q)$ Carboxylation
$(III)$ Benzaldehyde	$(iii)$ $(CH_3CO)_2O / CH_3COOK$	$(R)$ Substitution
$(IV)$ Phenol	$(iv)$ $NaOH / CO_2$	$(S)$ Haloform

$(1)$ For the synthesis of benzoic acid,the only $CORRECT$ combination is
$[A] (III) (iv) (R)$ $[B] (IV) (ii) (P)$ $[C] (I) (iv) (Q)$ $[D] (II) (i) (S)$
$(2)$ The only $CORRECT$ combination in which the reaction proceeds through radical mechanism is
$[A] (I) (ii) (R)$ $[B] (II) (iii) (R)$ $[C] (III) (ii) (P)$ $[D] (IV) (i) (Q)$
$(3)$ The only $CORRECT$ combination that gives two different carboxylic acids is
$[A] (IV) (iii) (Q)$ $[B] (III) (iii) (P)$ $[C] (II) (iv) (R)$ $[D] (I) (i) (S)$

$A$ primary alcohol was reacted with pyridinium chlorochromate $(PCC)$,which resulted in a product $P$. The product $P$ on treatment with ammoniacal silver nitrate solution produces:

Consider the following reactions. Total number of electrons in the $\pi$ bonds and lone pair of electrons in the product is:

Reduction of ketones cannot be carried out with which of the following reagents?