---- The battery in my cell phone is running low.

---- I _____ that last night before we went to bed.

A．was noticing

B．have noticed

C．had noticed

D．would notice

有以下程序
#include ＜stdio.h)
main()
char c1，c2；
c1='A'+'8'-'4'；
c2='A'+'8'-'5'；
printf("%c，%d\n"，c1，c2)；

已知字母A的ASCII码为65，程序运行后的输出结果是

A) E，68
B) D，69
C) E，D
D) 输出无定值