$CH_3CH_2COCH_3\overset{Y}{\longrightarrow} CH_3CH_2CH_2CH_3$

The reagent Y is

$NH_2NH_2, KOH,\, glycol$

The correct answer is Option (1) → $NH_2NH_2, KOH,\, glycol$

The reduction of aldehydes and ketones to alkanes. Condensation of the carbonyl compound with hydrazine forms the hydrazone, and treatment with base induces the reduction of the carbon coupled with oxidation of the hydrazine to gaseous nitrogen, to yield the corresponding alkane. Thus the reaction will be as follows:

This is not exactly a gentle process; heating to almost 200 °C is required to make the reaction occur at a reasonable rate.