Sentence Formation

The sentence requires a possessive pronoun. "His" is the correct possessive pronoun that indicates ownership or association with a male subject.

The correct collective noun for mules is "group." Therefore, "A group of mules" is the right sentence.

The correct phrase is "No sooner," as it is used in correlative conjunctions such as "No sooner did I reach the platform than the train started." This structure emphasizes the immediate sequence of actions.

Elephants make a sound called "trumpeting," which is why the correct word is "trumpets." It is a loud, distinctive sound made by elephants.