Which statement is true?()<br /> <img src="https://nimg.ppkao.com/2018-08/zhoulian/2018080116352954025.jpg?sign=a7c6d5098318cd9d6c3373cf24c542f5&t=62d2f580" />
A、The output could be 5-1,6-1,6-2,5-2
B、The output could be 6-1,6-2,5-1,5-2
C、The output could be 6-1,5-2,6-2,5-1
D、The output could be 6-1,6-2,5-1,7-1