The Clemmensen reduction of acetone yields

An organic compound $B$ is formed by the reaction of ethylmagnesium iodide $(CH_3CH_2MgI)$ with a substance $A,$ followed by treatment with dilute aqueous acid. Compound $B$ does not react with $PCC$ in dichloromethane. Identify $A$.

When ethanal reacts with $CH_3MgBr$ and $C_2H_5OH$/dry $HCl$,the products formed are

Which of the following transformations can be achieved using $Wolff-Kishner$ reduction conditions?

The compound that does not undergo haloform reaction is

$C_6H_5CHO + C_6H_5COCH_3 \xrightarrow[293 \ K]{OH^{-}}$ product of reaction is . . . . . . .