TOEFL Listening: TPO-TOEFL阅读TPO - S45IRP02KU1KD19HN$

Paragraph 7 supports which of the following ideas about fights over occupied nests? A. They are more violent than battles over unoccupied nest sites. B. They mostly occur between colonies over unoccupied sites. C. They are more frequent than battles over unoccupied sites. D. They last longer than battles over unoccupied sites do.