Tobacco is the second major cause of death in the world. It

Tobacco is the second major cause of death in the world. It is responsible for the death of one in ten *s worldwide(about 5 million deaths each year). If current smoking patterns continue, it will cause about 10 million deaths each year by 2020. Half the people that smoke today, that is about 650 million people, will finally be killed by tobacco. Which of the following statements is TRUE according to the first paragraph? A．Smoking causes 10 percent of the deaths worldwide. B．About 10 million people will die from smoking each year by 2020. C．Half the people in the world will be killed by smoking. D．There are about 1,300 million smokers nowadays. 为什么答案是D， Half the people that smoke today, that is about 650 million people, will finally be killed by tobacco.这句话怎么理解？为什么不可以？不是有这句话吗If current smoking patterns continue, it will cause about 10 million deaths each year by 2020.
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