题目

     The report came to the British on May 21, 1941. The German battleship Bismarck, the most powerful warship in the world, was moving out into the Atlantic Ocean. Her task: to destroy the ships carrying supplies from the United States to war-torn England.      The British had feared such a task. No warship they had could match the Bismarck in speed in firepower. The Bismarck had eight 15-inch guns and 81 smaller guns. She could move at 31 nautical miles (海里) an hour. She was believed to be unsinkable.However, the British had to sink her. They sent out a task force headed by t到南极考察的科学工作者，为了保护环境，除了必须把塑料以及金属类废弃物带离南极外，还必须把人体尿液、粪便等废物带离南极，这是因为南极A．缺少生产者B．分解者很少C．没有消费者D．缺乏必要的生活设施