The question asks us to identify which punctuation mark is used at the end of a question. To answer this, we need to understand the role of each punctuation mark provided in the options.
-
Full stop (.): This punctuation mark is used to indicate the end of a declarative sentence, a statement, or a command. It is not used for questions.
-
Comma (,): A comma is used to indicate a short pause within a sentence or to separate items in a list. It is not used at the end of a sentence or a question.
-
Question mark (?): This punctuation mark is specifically used at the end of a question. It indicates that the sentence is an inquiry. Therefore, this is the correct choice for ending a question.
-
Colon (:): A colon is used to introduce a list, a quote, or further explanation. It is not used at the end of a question.
In conclusion, the punctuation mark used at the end of a question is the Question mark (?).