—I spent two weeks in London last summer.
—Then you must have visited the British Museum during your stay, ________ you?
A:mustn't
B:haven'
C:didn't
D:hadn't
选项
陈述I
陈述II
A
Na2O2具有漂白性
Na2O2可用于潜水呼吸用氧
B
SiO2有导电性
SiO2可用于制作光导纤维
C
浓H2SO4有脱水性
浓H2SO4可用于干燥Cl2、SO2
D
CO有还原性
CO可用来冶炼生铁
如图是植物细胞和动物细胞的结构示意图,据图回答问题:(说明:中填图中序号,“横线”上填文字.)