Explanations:Prepositions are an essential part of the English language, used to express relationships between nouns, pronouns, and other parts of a sentence. In the context of the given sentence, the correct prepositions are "on" and "over." The sentence discusses Pakistan Prime Minister Imran Khan's bluster regarding Kashmir and the implied threat of a nuclear war.
The preposition "on" is used to indicate the specific topic of discussion. In this case, "on Kashmir" means that the bluster is about the issue of Kashmir. This usage of "on" is common when referring to a particular subject or topic. For example, one might say, "He gave a speech on climate change," where "on" indicates the topic of the speech.
The preposition "over" is used to indicate a level of importance or exaggeration. In the context of the sentence, "over the top" is an idiomatic expression that means excessive or exaggerated. This phrase is often used to describe something that is overly dramatic or extreme. For example, one might say, "His reaction was over the top," meaning that the reaction was excessively dramatic or exaggerated.
Other prepositions like "among" and "at" do not fit the context of the sentence. "Among" is used to indicate inclusion within a group, and "at" is used to indicate a specific point or location. Neither of these prepositions conveys the specific topic of discussion or the level of importance or exaggeration implied by the statement.
Understanding the correct usage of prepositions is crucial for effective communication in English. It is important to choose the preposition that best fits the context and conveys the intended meaning accurately. In this case, "on" and "over" are the most appropriate choices to convey the specific topic of discussion and the level of importance or exaggeration implied by the statement.