人口负担系数是指人口中非劳动年龄人口数与劳动年龄（15-64岁）人口数之比。人口生理密度是指适合于农业用地的单位面积上的人口数。左图是我国某市人口普查的年龄构成图，右图是该市人口密度与人口生理密度统计图。读图分析回答下题。
按常住人口计算，该市人口负担系数较重（约为40％），但该市却是我国主要的劳务输出地区之一，这说明该市（ ）
①人口自然增长较快 ②人口机械迁移以迁出为主
③人口合理容量减小 ④人口老龄化趋势较为突出
A．①②
B．①③
C．②④
D．③④
答案：C
题目分析：
根据人口负担系数概念可知，人口负担系数重说明非劳动人口多或劳动年龄人口少，该市却是我国主要的劳务输出地区之一，说明人口以迁出为主，老龄化趋势突出，故选C项。
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| When Pat Jones finished college, she decided to travel around the world and see as many foreign places as she could 1 she was young. Pat wanted to visit Latin America first, so she got a job 2 an English teacher in a school in Bolivia. Pat spoke a little Spanish, 3 she was able to communicate with her students even when they didn't 4 much English. A sentence she had read somewhere was in her mind: if you dream 5 a foreign language, you have really mastered (掌握) it. Pat repeated this sentence to her students and hoped that some day she would dream in Spanish and they would dream in 6 . One day, one of her 7 students came up and explained in Spanish that he had not done his homework. He had gone to bed early and had slept 8 . "What does this have to do with your 9 ?" Pat asked. "I dreamed all night, Miss Jones. And my dream was in English." "In English?" Pat was very 10 , since he was such a bad student. She was 11 secretly jealous (嫉妒的). Her dream was still not in Spanish. But she encouraged (鼓舞) her young student,"Well, 12 me about your dream." "All the people in my dream 13 English. All the newspapers and magazines and TV programs were in English." "But that's 14 ,"said Pat. "What did all the people say to you?" "I'm sorry, Miss Jones. That's 15 I slept so badly. I didn't understand a word they said. It was a nightmare (噩梦)!" | ||||
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