6. Five students dressed up as the Olympic mascots Beibei, Jingjing, Huanhuan, Yingying, and Nini, and lined up to perform a program. If Beibei and Nini do not stand next to each other, there are ( ) different arrangements.
(A) 48
(B) 72
(C) 96
(D) 120
6、B
Solution: The number of arrangements where Bei Bei is on the left and Ni Ni is on the right adjacent to each other is $4 \times 3 \times 2 \times 1=24$ (ways), and the number of arrangements where Bei Bei is on the right and Ni Ni is on the left adjacent to each other is also $4 \times 3 \times 2 \times 1=24$ (ways). The total number of arrangements is $5 \times 4 \times 3 \times 2 \times 1=120$ (ways). Therefore, the number of arrangements where Bei Bei and Ni Ni are not adjacent is $120-2 \times 24=72$ (ways).