以下哪种工艺可以不设二沉池（）
A.AB法
B.氧化沟工艺
C.生物接触氧化法
D.曝气生物滤池
参考答案：D
— Oh, this cartoon book is very interesting. Where did you buy ____? I want to buy _____, too.
— In the bookshop near my home.
A．one; one
B．it; it
C．it; one
D．one; it
松木品种较多，来源广泛，一般都有树脂道，且能发出松脂香味。
