The nucleophilic addition reactions of group are catalyzed by bases or acids. An acid catalyzed reaction:

Explanation

Option B is correct.The nucleophilic addition reactions of carbonyl groups are catalyzed by bases or acids. Base-catalyzed nucleophilic addition reactions In a base-catalyzed nucleophilic addition reaction, the base abstracts a proton from the carbonyl group, creating a negatively charged carbonyl carbon. This makes the carbonyl carbon more electrophilic, and it is more likely to be attacked by a nucleophile. The following reaction is an example of a base-catalyzed nucleophilic addition reaction: RCHO + H2O → R-C(OH)2 Here, RCHO is the starting compound, H2O is the nucleophile, and H+ is the leaving group. Acid-catalyzed nucleophilic addition reactions In an acid-catalyzed nucleophilic addition reaction, the acid protonates the carbonyl oxygen, creating a positively charged carbonyl oxygen. This makes the carbonyl carbon less electron-rich, and it is less likely to be attacked by a nucleophile. However, the positively charged carbonyl oxygen is also a good leaving group, and it can be easily displaced by a nucleophile. The following reaction is an example of an acid-catalyzed nucleophilic addition reaction: RCHO + NH3 → R-CH=NH Here, RCHO is the starting compound, NH3 is the nucleophile, and H+ is the leaving group.