Which of the following is an example of a coordinating conjunction?

A coordinating conjunction is used to join words, phrases, or clauses that are of equal grammatical rank. In this case, "and" serves as a linking word that connects elements in a sentence, such as combining two nouns, two verbs, or two independent clauses. For example, in the sentence "I want to buy apples and oranges," "and" connects the two nouns.

The other choices—"although," "because," and "unless"—are examples of subordinating conjunctions. They introduce dependent clauses and indicate relationships between clauses, but they do not coordinate equal grammatical structures. "Although" introduces a contrast, "because" indicates a cause, and "unless" introduces a condition. This distinction is crucial in understanding the function of coordinating versus subordinating conjunctions in sentence structure.