<u>The correct answer is: B. after the gazelle
</u>
In the sentence: The cheetah runs quickly after the gazelle, the phrase after the gazelle corresponds to a prepositional phrase that is defined as a group of words that begins with a preposition and ends in a noun, a pronoun or a nominal phrase.
The phrase in the given sentence is "after the gazelle". The correct answer is option B. This phrase is an example of an object of the preposition. The word "after" is a preposition and its object is the word, "gazelle".
