阅读下面的对话完成任务。

A: Excuse me, Susan. （1）Is this your backpack?

B: No, it isn't. It's Jack's. （2）My backpack is green.

A: Is your computer game in the lost and found case?

B: No, it's Jack's. And that white eraser is Jack's, too.

A: Do you know Jack?

B: Yes, I do. （3）他是一个英国男孩。He's in Class One, Grade Seven.

A: Oh, what's his telephone number?

B: 100-2116

A: Is Miss Miller his English teacher?

B: Yes, you're right.

①图①是人体平静呼吸时，肺容量变化示意图，图中c→d段表示呼气过程，膈肌舒张

②当光照强度达到图②中b 点时，植物开始进行光合作用

③当环境温度降低时，图②中的a点下移

④图③表示菜豆种子萌发及幼苗长成植物体过程中，有机物含量变化．

下列微粒结构示意图中，表示阴离子的是（  ）