Which punctuation mark is used at the end of a question?

The question mark is specifically designed to indicate that a sentence is a question. It signals to the reader that the statement preceding it is interrogative, inviting a response or requiring further information. This punctuation mark is crucial in differentiating questions from other types of sentences, ensuring clarity in communication. For example, in the sentence "Are you coming to the party?", the question mark at the end indicates that the speaker is seeking a response regarding attendance. Other punctuation marks serve different functions: an exclamation mark denotes strong emotion or emphasis, a comma provides a pause or separates elements within a sentence, and a period signifies the end of a declarative statement. Each punctuation mark has its unique role in sentence structure and meaning, but the question mark's sole purpose is to indicate inquiries.