A．The terrible conditions in Antarctica.

　　B．A special fish living in freezing waters.

　　C．The ice shelf around Antarctica.

　　D．Protection of the Antarctic cod.

　　【解析】　主旨大意题。从第一段第二句话 At the underside of the shelf there lives a small fish，the Antarctic cod.和第二段第二句话 How does it live where most fish would freeze to death？可推知B项最佳。

　　【答案】　B

　　2．Why can the Antarctic cod live at the freezing temperature?

　　A．The sea water has a temperature of －1.88℃.

　　B．It loves to live in the ice­salt mixture.

　　C．A special protein keeps it from freezing.

　　D．Its blood has a temperature lower than－2.05℃.

　　【解析】　推理判断题。从第五段最后两句When it was removed，the blood froze at sea water temperature.When it was put back，the blood again had its antifreeze quality and a lowered freezing point.可知答案为C。

　　【答案】　C

　　3．What does the underlined word "it" in Paragraph 5 refer to?

　　A．A type of ice­salt mixture.

　　B．A newly found protein.

　　C．Fish blood.

　　D．Sugar molecule.

　　【解析】　词义猜测题。从本段的Their search led to some really strange thing made up of a protein(蛋白质) never before seen in the blood of a fish.可推知答案为B。

　　【答案】　B

4．How do the scientists carry out their research?