Our waste recycling project ________ a lot of investigation and paperwork had been done by the end of last term.

A．involved

B．to involve

C．being involved

D．involving

台站应备齐的工具书包括（）.

A.地面气象观测云图

B.常用表2、3号和湿度查算表及手工查算流程

C.本站气压简表及查算办法

D.《地面气象测报业务系统软件操作手册》