$CH_3-CO-CH_2-COOH$ $\xrightarrow{\Delta} X$ $\xrightarrow[OH^-]{HCN} Y$,$Y$ is:

Comment on the stereochemistry of the products for the following reaction:
$3$-methylpentan-$2$-one + $CH_3MgBr$ followed by $NH_4Cl$ workup.

Which of the following gives an alcohol and salt of carboxylic acid when reacted with conc. $NaOH$?

The end product in the reaction is:

An organic compound $(X)$ with molecular formula $C_3H_6O$ is not readily oxidised. On reduction it gives $(C_3H_8O)$ $(Y)$ which reacts with $HBr$ to give a bromide $(Z)$ which is converted to a Grignard reagent. This Grignard reagent on reaction with $(X)$ followed by hydrolysis gives $2,3-$dimethylbutan$-2-$ol. Compounds $(X)$,$(Y)$ and $(Z)$ respectively are $:$

Assertion : Hydroxyketones are not directly used in Grignard reaction.
Reason : Grignard reagents react with hydroxyl group.