单选题 You ______ sick for five days. Maybe you should see a doctor.
A. will be B. are
C. were D. have been

【正确答案】 D
【答案解析】[解析] 表达从5天前到现在持续的情况,最合适的时态是现在完成时。主语是第二人称,因此D项have p.p.是正确答案。