A:本能
B:先天性行为
C:学习行为
D:聪明才智
读我国西气东输工程示意图(如下图),完成下列问题。
More and more people in cities want to live in the countryside because they are ______ the noisy city life.
种群的年龄组成大致可分为图示a、b、c三种类型,据图分析,下列表述不正确的是( )