The air of countryside is cleaner than () of city, but I don't like to live () far.

A．it; that

B．one; very

C．that; that

D．one; that

碘的良好来源是（）

A、牛肉、粉丝、藕

B、海带、紫菜、鱼类

C、猪肝、鱼、萝卜