目前有部分学生在做作业或考试时，喜欢用修正液（涂改液），经实验证明，修正液含有多种挥发性有害物质，三氯乙烷（CH3CCl3），就是其中的一种，吸入这些有害物质后易引起头晕、头痛，严重者会呼吸困难、抽搐。下面关于三氯乙烷的几种叙述中正确的是[ ]
A.由碳、氢、氯三种元素组成的化合物
B.它的分子中碳、氢、氯元素的原子个数比为1：3：3
C.它的相对分子质量为CH4的6倍
D.它是冰箱中常用的制冷剂
A
根据短文内容，从各题所给的A、B、C、D四个选项中选出最佳选项。 “Never give up!” It is my law(法则) of life. It has brought me ____. I learned the law from my father's ____ story. My father was ____ in a poor village in the north of Jiangsu，in China. When he was a young boy，he went to school in the morning，then ___ in the fields till sunset. And then he did his homework ____ midnight. Life was hard，because they had no ___！ At the age of 14，my father heard of the United States of America. It was the land of gold，the land where ____ people can become rich. “____ don't I go to America？” he thought to himself，full of hope. So，my father came to America. “I had thought it was easy to ____ money in America，” he told me. “But when I arrived there，I realized it was not true. They did not like to hire(雇佣) me because I spoke ____ English. Later，I worked in a small restaurant，cleaning up tables，____dishes and sweeping the floor. Life was ____ for the first few years. I worked from 10 a. m. to 11 p. m. I wanted to go to school to learn English，but it was impossible. I couldn't ____ the schooling(学费). ” My father ____ working hard，and reached his goal. “Alan，” he often says to me. “If you want something，you have to work for it and never give up. Things do not come ____ in life. ” That is what I learned from my father.
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