补肾阳，益精血，强筋骨，调冲任，托疮毒的药物是( )
A．蛤蚧
B．鹿茸
C．狗脊
D．补骨脂
E．人参
参考答案：B
右图是某同学设计的趣味实验装置，其气密性良好。
若将胶头滴管中的物质滴入锥形瓶后，能明显观察到U形管中红墨水的液面左低右高，甚至从右端溢出。请推测胶头滴管和锥形瓶中的物质分别是什么？（答出两种组合即可）
It's suggested that some activities ________ to celebrate the 30th anniversary of the Reform and Opening up.
A．should hold
B．are held
C．be held
D．will be held
