Which word is used to link sentences, clauses, or phrases?

The correct choice is pertinent because a conjunction is specifically defined as a word that connects sentences, clauses, or phrases. It serves the purpose of providing coherence and allowing the flow of thoughts within a sentence or across multiple sentences. For example, in the sentence "I wanted to go for a walk, but it was raining," the conjunction "but" links two independent clauses, showing the contrast between the two ideas.

In contrast, adjectives describe nouns, adding detail or clarification about the characteristics of a person, place, or thing. Verbs indicate actions or states of being, playing a crucial role in constructing the main part of a sentence. Adverbs modify verbs, adjectives, or other adverbs, often providing more information regarding how, when, where, or to what extent an action is performed. While all these parts of speech contribute to the richness of language, it is the conjunction that uniquely serves the function of linking disparate elements, making it the correct choice in this instance.