Which sentence correctly uses commas?

The chosen answer is correct because it uses commas to appropriately separate items in a list, following the rules of standard written English. In this instance, the sentence lists three fruits: apples, oranges, and bananas. The commas are placed after "apples" and "oranges," and before the conjunction "and," which properly organizes the items in the series. This use of the Oxford comma, or serial comma, before the conjunction is often preferred for clarity, ensuring that all items are clearly listed and easily understood by the reader.

In contrast, the other options lack the necessary clarity or follow improper punctuation rules. For example, omitting commas entirely, as seen in the first choice, leads to confusion about where one item ends and another begins. The second choice includes a comma after "oranges" but not before "and," which can imply that "oranges and bananas" are a single item rather than two distinct items. The fourth choice incorrectly places a comma after "are," which disrupts the structure of the sentence and can confuse the reader regarding the subject of the sentence.