Reaction of formaldehyde and ammonia gives

Trichloroacetaldehyde was subjected to Cannizzaro's reaction by using $NaOH$. The mixture of the products contains sodium trichloroacetate and another compound. The other compound is:

$A$ in the above reaction is:

The reaction of an aldehyde with hydroxylamine gives a product which is called

The correct option for the above reaction is

Tollen's reagent and Fehling solutions are used to distinguish between