1. [单选题]芯片8255A的端口B工作在方式1输出时，为了能利用INTRB信号向外发中断信号，下列正确的置位/复位控制字是
A. 05H
B. 06H
C. 07H
D. 08H
2. [多选题]我们经常使用的压缩软件是______。
A. Excel
B. IE
C. WinRAR
D. Word
3. [单选题]N-S diagram can used to substitute conventional program flow Chart．In the following phrases，Which does not belong to the basic control structures that contain?
A. sequence structure
B. condition Structure
C. selection structure
D. execution structure
