Which of the following reagents can be used to reduce the $ > C = O$ group to $CH_2$?

Assertion : Aldol condensation can be catalysed both by acids and bases.
Reason : $\beta$-Hydroxyaldehydes or ketones readily undergo acid-catalysed dehydration.

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

Match the reactants in Column-$I$ with the major products in Column-$II$ obtained after the reaction.

Column-$I$ (Reactants)	Column-$II$ (Major Product)
$A$. $HCHO \xrightarrow{(i) CH_3MgBr, (ii) H_2O}$	$i$. $C_6H_5CHOHCH_3$
$B$. $C_6H_5CHO \xrightarrow{(i) CH_3MgBr, (ii) H_2O}$	$ii$. $(CH_3)_3COH$
$C$. $CH_3COCH_3 \xrightarrow{(i) CH_3MgBr, (ii) H_2O}$	$iii$. $CH_3CHOHCH_3$
$D$. $CH_3CHO \xrightarrow{(i) CH_3MgBr, (ii) H_2O}$	$iv$. $CH_3CH_2OH$

The major product of the following reaction is:

What is the product obtained in the reaction?
$CH_3-CH=CH-CH_2-CHO \xrightarrow[(ii) H_3O^{+}]{(i) LiAlH_4} \text{product}$