下列选项中，不是气管和支气管的主要生理功能的是（）

A.呼吸调节功能

B.清洁功能

C.防御性咳嗽反射

D.免疫功能

E.换气功能

What are the plans of Wal-mart in China().

A. To buy the retail stores of Trust-Mart.

B. To allow the presence of labor unions into Wal-Mart.

C. To become the biggest food and department store network.

D. All except c.