The reaction shown below proceeds via which mechanism?

Predict the product when the given compound $(A)$ reacts with $NaBH_4$.

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 $:$

$Propanal$ on treatment with dilute sodium hydroxide forms:

The increasing order of the equilibrium constant for the formation of a hydrate from the following compounds is:

Which of the following will not give the iodoform test?