Depression is very common in modern society. ________ 1 in every 33 children may have depression; in teens, that number may be ________ 1 in 8.

A．As little as; as low as

B．As many as; as much as

C．As many as; as high as

D．As few as; as low as

家庭中最持久的次系统为（）三个次系统

A.夫妻

B.祖孙

C.亲子

D.手足