A-A+
The relative stability of the human population
问题详情
The relative stability of the human population has been upset by ______.
A．the proportion of the reproductive age group
B．the influenza epidemic
C．advances in medical science
D．the Black Death in Europe
参考答案
正确答案：C
解析：见第三段“The relative stability of the human population has been upset by advances in medical science.”
