I believe the answer is going to be A but without the underlined phrase I am not 100% sure.
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The only option which contains a dialog is C. <span>C.IAN. Where have you been?SAM. Here you can see two people that participate in conversation which a direct characteristic of a dialogue. A dialogue must have a topic and two or more people to discuss on it. The rest of options just contain simple statements. </span></span>
