听力原文： Antarctica is the fifth largest of the Earth's seven continents. It surrounds the South Pole, the point at the southern end of the Earth's axis. Antarctica has no permanent human population because it is almost completely covered by ice. Antarctica is shaped somewhat like a comma, with a round body surrounding the South Pole and a tail curving toward South America. Antarctica lies 1,000 km (600 mls) from South America, its nearest neighbor; 4,000km(2,500 mls) from Africa; and 2,500 km (1,600 mls) from Australia. Antarctica's latitude and high elevations make it the coldest continent in the whole world.
Antarctica was first discovered in the early 19th century, and because of the extreme cold and the lack of native peoples, forests, land animals, and obvious natural resources, the continent remained largely neglected for decades. Scientific expeditions and seal hunters had explored only parts of its coasts by the end of the 19th century, while the interior remained unknown. Explorers first reached the South Pole in 1911, and the first permanent settlements—scientific stations—were established in the early 1940s. From that time the pace of exploration accelerated rapidly. Scientists continue to conduct research in Antarctica, and in recent years increasing numbers of tourists have visited Antarctica to appreciate the region's majestic scenery and wildlife.
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A. North America.
B. South America.
C. Africa.
D. Australia.