The school rule states that no child shall be, unless        _by an adult, allowed out of the school during the day.

A．to be accompanied

B．accompanying

C．accompanied

D．being accompanied

有以下程序：
#include＜stdio．h＞
union pw
int i;
char ch[2]；
a；
main()
a.ch[0]=13；a.ch[1]=0；printf("%d\n"，a．i)；
程序的输出结果是( )。

A．13

B．14

C．208

D．209