题目

阅读理解 Astronomy (天文学) is the oldest science known to man. Thousands of years ago man looked at the stars and wondered about heavens(天堂). But the six planets that he could see with his eyes alone limited man. The Greeks studied astronomy over 2,000 years ago. They could see the size, color, and brightness of a star. They could see its place in the sky. They watched the stars move as the seasons changed. But the Greeks had no tools to help themselves study the heavens. Each new tool added to the field of astronomy helped man reach out into space. Until there were telescopes(望位于第二级阶梯，且人口最多的盆地是（　　）A. 塔里木盆地 B. 四川盆地 C. 准噶尔盆地 D. 柴达木盆地 B 【解析】试题分析：我国有四大盆地，位于第二级阶梯的是四川盆地、塔里木盆地、和准噶尔盆地，四川盆地海拔最低，气候最好人口最多。所以选B。