The world's fifth largest continent, and its most remote, is also the coldest, windiest, and driest continent — the last a seeming contradiction ( 自相矛盾 ) because two percent of the Earth's fresh water is in Antarctica ( 南极洲 ). It just happens to be locked up in the continent's icecap, which is between 6,000 and 14,000 feet thick and contains 90 percent of the world's ice. With no native or permanent population, it is certainly the loneliest continent. And it is the only continent to have been truly "discovered", since nobody lived there when it was found. Centered on the South Pole and lying almost entirely within the Antarctic Circle, Antarctica has an area of more than 5.5 million square miles, equal to 10 percent of the Earth's land suce. Since its discovery in 1820, Antarctica has been the focus of competing claims for what may be inaccessible riches. Only once has there been actual fighting over the region. In 1952, British scientists were attacked by Argentine soldiers ordered to pr the British from rebuilding a destroyed scientific base. They were fighting over the Antarctica Peninsula, a long finger of land that reaches up toward the tip of South America, only 800 miles away. The British based their claim on their possession of the Falklands, a group of islands about 450 miles northeast of Cape Horn at the tip of South America. During the 1950s, Australia, New Zealand, France, Norway and Chile also laid claim to Antarctica region. The United States, the Soviet Union, Japan, South Africa and Belgium established research stations by 1959. Although there is a supposition of large mineral wealth and oil resources under the ice and in the seas around the continent, the demanding climate, deepness of tremendous ice, and easily damaged environment put unusually great obstacles in the way of recovering any of that supposed wealth. Since 1961, Antarctica has been governed by the Antarctica Treaty ( 条约 ), which declared that the continent be only used for peaceful purposes, allowed no war actions, and established the continent as the world's first nuclear-free zone ( 无核区 ). 26. According to the passage, Antarctica's dry climate is ________. A) perfectly normal for such a large area of land B) a shame because of so much fresh water there C) related to the thickness of the icecap D) determined by its remoteness from other continents 27. Which of the following statements is TRUE? A) Antarctica was a region totally without inhabitants at the time of its discovery. B) Antarctica has been fought over many times. C) No other continent has been claimed by so many countries. D) No one knows where the native population came from. 28. Various nations have laid claim to Antarctica ________. A) because they desire land for further population expansion B) due to the easily obtainable mineral wealth there C) in hopes of gaining access to the natural resources there D) purely for the sake of conducting scientific researches 29. Competing claims for shares of the continent ________. A) were recognized in the 1961 Antarctica Treaty B) resulted in war action on one occasion C) were given up when the treaty was assigned D) have become stronger in recent years 30. According to the passage, Antarctica is ________. A) in the control of a group of four European countries B) still being used for secret exercises C) going to be opened up to further land claims D) protected from development for war purposes