---Dave! Your mom is too busy! You shouldn’t throw your waste things

everywhere!

---Oh. I am sorry. I am going to_________ and put them in the waste box.[ ]

A. take out the trash

B. make the desk clean

C. fold my clothes

D. do some shopping

计算机操作系统的功能是( )。 ①把源程序代码转换为目标代码 ②实现计算机用户之间的相互交流 ③完成计算机硬件与软件之间的转换 ④控制、管理计算机系统的资源和程序的执行

A．①和②

B．③和②

C．②和④

D．③和④