若以下程序所生成的可执行文件名为filel.exe，当执行该程序时输入FILE1 CHINA BEIJING SHANGHAI，程序的输出结果是______。
main (int argc，char* argv[])
while(--argc＞0) ++argv；printf("%s"，*argv)；

A) CHINA BEIJANG SHANGHAI
B) FILE1 CHINA BEIJNG
C) CBS
D) FCB

Carbon dioxide as a fire fighting agent has which advantage over other agents?（）.

A.It causes minimal damage

B.It is safer for personnel

C.It is cheaper

D.It is most effective on a per unit basis