令人满意的

Some biologists say this is caused by the "selfish gene."

一些人类学家认为这是&自私基因&引起的。

Riders must register as a category but may ch oose to participate in either the individual time trial, the team time trial, or both.

可以只参加个人计时赛或团队计时赛，或者两个都参加。