Which among the following reagents is used in the Rosenmund reduction?

$CH_3CH_2C \equiv N \xrightarrow{X} CH_3CH_2CHO$. The compound $X$ is:

Which of the following represents the Etard reaction?

The reduction reaction shown is known as:

An organic compound $X$ gives a red precipitate on heating with Fehling's solution. Which one of the following reactions yields $X$ as a major product?

Identify the product $B$ in the following sequence of reaction: $CH_3MgBr$ $\xrightarrow{CdCl_2} A$ $\xrightarrow{CH_3COCl} B$