Which two statements are true?()<br /> <img src="https://nimg.ppkao.com/2018-08/zhoulian/2018080116463355356.jpg?sign=d264f2b0a2f9dc2a239cc9178445fad3&t=62d358c5" />
A、The output could be 8-1,7-2,8-2,7-1
B、The output could be 7-1,7-2,8-1,6-1
C、The output could be 8-1,7-1,7-2,8-2
D、The output could be 8-1,8-2,7-1,7-2