The polymer shown in the image is obtained when a carbon compound is allowed to stand. It is a white solid. The polymer is:

Assertion $(A)$: Aldehydes are more reactive than ketones towards nucleophilic addition reactions.
Reason $(R)$: In aldehydes,carbonyl carbon is less electrophilic compared to ketones.
The correct answer is

Which carbonyl group is most reactive for $NAR$ (Nucleophilic Addition Reaction)?

What are $A, B, C$ and $D$ in the following cross-aldol condensation reaction?
$\text{Propanal} + \text{Ethanal} \xrightarrow[ii) \ \Delta]{i) \ NaOH} A + B + C + D$
(The products are the four possible $\alpha,\beta$-unsaturated aldehydes formed by self and cross-aldol condensation followed by dehydration.)

Which of the following will show the haloform reaction?

What is the main product obtained by the cross-aldol condensation of benzene carbaldehyde and $1$-phenyl ethane$-1$-one?