Let's analyze the given statements in detail:

Statement I: Acidity of $$\alpha$$-hydrogens of aldehydes and ketones is responsible for Aldol reaction.

This statement is correct. The presence of acidic $$\alpha$$-hydrogens in aldehydes and ketones makes it possible for these compounds to undergo deprotonation, forming enolates. These enolates can then attack the carbonyl carbon of another aldehyde or ketone, leading to the formation of the Aldol product. Therefore, the acidity of the $$\alpha$$-hydrogens is crucial for the Aldol reaction.

Statement II: Reaction between benzaldehyde and ethanal will NOT give Cross-Aldol product.

This statement is incorrect. Benzaldehyde (which lacks an $$\alpha$$-hydrogen) can indeed react with ethanal (which has an $$\alpha$$-hydrogen) in a Cross-Aldol reaction. In a Cross-Aldol reaction, one molecule (ethanal) forms an enolate and reacts with another molecule (benzaldehyde), resulting in the formation of a Cross-Aldol product.

Based on these explanations, the most appropriate answer is:

Option B

Statement I is correct but Statement II is incorrect.