Concept:Commands, or imperatives, require a special question tag to show politeness. For such sentences, the tag used is "will you?"Explanation:The given sentence, "Put the books on the shelf," gives a direct order. It is an imperative sentence, not a statement. In English, an imperative sentence does not use the same question tags as ordinary statements. Tags like "do you?" and "have you?" are used with present tense or present perfect statements, not with commands. When we want to soften a command or make a polite request, we attach the tag "will you?" to the imperative. Therefore, the sentence becomes: "Put the books on the shelf, will you?" This tag asks the listener for agreement or compliance. The other options are grammatically incorrect in the context of an imperative.Answer:C. will you