Zheng He, a Ming dynasty explorer,       illness on his way back to China from Africa in 1433.

A. lived on               

B. tried out              

C. died of

处方开具当日有效，特殊情况下可以延长有效期，但有效期最长不得超过（）

A.2天

B.3天

C.5天

D.7天

E.10天