单项选择题 准备发放会议文件时，不能有多少与会者就准备多少份，要留有一定以备临时增加与会者。

判断题 Read the research article entitled 'Putting a Price on Ecosystem Services' (see Reading Text 1 in the file "Language input from reading texts") and answer the following question. The author gives social contexts. (Note: Social context refers to the environment of the society and its structure in which a particular event happened, reflecting how people interact in that environment.) A、正确 B、错误

未知题型 下列程序的输出结果是( )。 #include＜stdio.h＞ int fun(int x) { int a; if(x==0‖x==1) return 3; else a=x-fun(x-2); return a; } void main() { printf('%d',fun(7)); }A.2B.8C.9D.5