The product formed by the reaction of an aldehyde with a primary amine is

An organic compound $A$ reacts with methyl magnesium iodide to form an addition product,which on hydrolysis gives compound $B$. Compound $B$ gives a blue color in the Victor Meyer test. What are compounds $A$ and $B$ respectively?

Least reactive towards nucleophilic addition is

What will be the product $B$ in the following sequence of reactions?
$HC \equiv CH$ $\xrightarrow{30\% \, H_2SO_4, \, HgSO_4} A$ $\xrightarrow{NaOH} B$

Which of the following is the correct statement for the given reaction?
$CH_3-CH=O + C_6H_5-CH=O \xrightarrow[\Delta]{OH^{\ominus}(aq)} X_{(C_4H_6O)} + Y_{(C_9H_8O)}$

What are the products formed when a mixture of benzaldehyde and formaldehyde is heated with an aqueous solution of $NaOH$?