Which of the following author names may not be the right format of the reference?

、 X. Guan, Zhang, S., S. Li, Wu Wang.
B、 Guan, X, Zhang, S., Li, S., Wang, W.
C、 Xiaohong Guan, S. Zhang, S. Li, Wang, W.
D、 Guan Xiaohong, Zhang, S., S.Li, W.Wang.