Which of the following on reaction with Grignard reagent followed by hydrolysis forms a tertiary alcohol?

What is the product obtained in the reaction of acetaldehyde with semicarbazide?

The product $(B)$ is:

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
$[A] (IV) (iii) (Q)$ $[B] (III) (iii) (P)$ $[C] (II) (iv) (R)$ $[D] (I) (i) (S)$

Which of the following reagents will convert isobutyraldehyde to the corresponding acid?

$I. HNO_3$	$II. NH_2NH_2 / OH^-$
$III. 2[Ag(NH_3)_2]^+$	$IV. NaOH$

Which of the following reagents is used for the following conversion?
$CH_3-CH=CH-CHO \longrightarrow CH_3-CH=CH-CH_2OH$