假如某生态系统只有甲、乙、丙三种生物,他们的捕食关系如图所示,那么该生态系统中的杂食性动物是( )
A:甲
B:乙
C:丙
D:甲和丙
⑴My favourite song is the ABC song.____
⑵Tom goes to the zoo on Saturdays.____
⑶Look at the dog. It's thin.____
⑷The sweater is on the bed.____
⑸—What are they? ____
—They're trees.
A. B. C. D. E.
和平与发展是当今世界的两大主题,它们的关系是( )
①两者相辅相成 ②和平是发展的前提条件
③发展是实现和平的重要基础 ④两者是一回事