—Look! More trees are being planted around the new building. What do you think of  ________ natural surroundings here?

—Fantastic! Beyond ________ expression.

A．the; /

B．the; the

C．/; /

D．the; an

工程项目管理组织结构中，（）是指从事和完成具体任务的阶层。

A.操作层

B.执行层

C.决策层

D.协调层