Benzaldehyde on heating with concentrated $NaOH$ gives:

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

Reduction of ketones cannot be carried out with which of the following reagents?

Arrange the given gem-diols in decreasing order of their stability.

Given below are two statements: Consider the following reaction: $R_2C=O + H_2O \rightleftharpoons R_2C(OH)_2$.
Statement $I$: In the case of formaldehyde $(HCHO)$,$K_{eq}$ is about $2280$,due to small substituents,hydration is faster.
Statement $II$: In the case of trichloroacetaldehyde $(CCl_3CHO)$,$K_{eq}$ is about $2000$ due to the $-I$ effect of $-Cl$ atoms.
In the light of the above statements,choose the correct answer from the options given below:

Which one of the following pairs is not correctly matched?