“蚁穴溃堤”这一成语主要揭示了（　　）

A．环境对生物的影响

B．生物对环境的影响

C．生物利用环境

D．生物适应环境

— What’s Tom’s dream?

— Tom’s dream is to trek      the jungle, but Jack would like to sail     the ocean.

A．through, through

B．through, across

C．across, across

D．across, through