Which one of the following gives a yellow precipitate with iodine and $NaOH$ solution?

This conversion can be achieved by

Benzalacetone is the product of mixed aldol condensation between benzaldehyde $(C_6H_5CHO)$ and acetone $(CH_3COCH_3)$. What is its structure?

Which of the following is the structural formula of mesityl oxide?

Consider the following sequence of reactions.
$C_6H_5COONa$ $\xrightarrow[\Delta]{NaOH/CaO} X$ $\xrightarrow[\text{Anhy. } AlCl_3]{CO/HCl} Y$ $\xrightarrow[NaOH]{\text{conc. }} A + B$.
If $A$ is the reduction product of $Y$,what is $B$?

Which reagent is used to distinguish between acetaldehyde and acetophenone?