欧洲流经国家最多的国际性河流是[ ]
A．多瑙河
B．莱茵河
C．鲁尔河
D．塞纳河
答案：A
下述哪项政策属于健康促进公共政策
A．环境保护法B．公共场所禁止吸烟规定C．A+BD．传染病防治法E．B+C
The average age at which people begin to need eyeglasses vary considerably.
A．varies
B．is varied
C．will vary
D．has been varied
