S1:Chief officer,how do you deal with the plastic waste on board daily? S2:We usually burn it in the incinerator at sea,when we're in a port,the garbage will be delivered ashore.We have got a detailed record in the Garbage Record Book. Q:What are the two speakers talking about? A. They are talking about the issue of plastic garbage disposal. B. They are talking about the pollution by plastic waste. C. They are talking about delivering the plastic waste ashore. D. They are talking about the recording of garbage disposal.