我国濒临的四大海域中最南端的是（ ）
A：黄海
B：东海
C：渤海
D：南海
在晴朗的冬夜，农民用熏烟的方法防止霜冻、是因为（ ）
—I think teenagers should be allowed to make their own decisions when they have problems at school.
—_______. They're not calm enough, after all.
下列动物不具有社会行为的是（ ）
