Which of the following can NOT be inferred from the passa.ge?

Which of the following can NOT be inferred from the passa．ge？ 查看材料

A.Birds do not migrate at the same time．

B.Birds usually follow regular routes of migration．

C.Each species has a special reason for migration．

D.Birds migrate to their own particular places every year．

请帮忙给出正确答案和分析，谢谢！