第22题: [单项选择]In this passage, what does the term "coalescence" refer to A. The gathering of small clouds to form larger clouds. B. The growth of droplets. C. The effect of gravity on precipitation. D. The movement of dust particles in the sunlight. 参考答案:B 答案解析:文章结尾处点明the growth of a cloud...is called "coalescence"。