Interpretation of the statements

The question is about the hydration of aldehydes to form gem-diols: $RCHO + H_2O \rightleftharpoons RCH(OH)_2$

The quantity referred to in both statements is the equilibrium constant of hydration (commonly denoted $K_h$).

General trend in hydration of aldehydes

Hydration is favored when:

• the carbonyl carbon is more electrophilic, and/or
• steric hindrance around the carbonyl carbon is small.

Thus:

• small groups increase hydration,
• electron-withdrawing groups increase hydration strongly.

Check Statement (I): Formaldehyde

For formaldehyde, the reaction is: $HCHO + H_2O \rightleftharpoons CH_2(OH)_2$

Formaldehyde has two hydrogens attached to the carbonyl carbon, so:

• steric hindrance is minimal,
• nucleophilic attack by water is easy,
• hydration is strongly favored.

The hydration constant for formaldehyde is indeed very large (about $2280$).

Therefore, Statement (I) is true.

Check Statement (II): Trichloroacetaldehyde (chloral)

Trichloroacetaldehyde is $CCl_3CHO$.

The $-I$ effect of the three chlorine atoms strongly withdraws electron density, making the carbonyl carbon highly electrophilic. Hence water adds readily: $CCl_3CHO + H_2O \rightleftharpoons CCl_3CH(OH)_2$

Its hydration constant is also very large, around $2000$.

Therefore, Statement (II) is true.

Conclusion

Since both statements are correct, $\boxed{\text{Option B}}$

Comparison with stored answer

Stored correct answer = B.

My derived answer = B.

Hence, the derived answer agrees with the stored answer.