题目：
Why does the author mention fresh coffee in Paragraph 2
A．As an example of complex substances having not been duplicated satisfactorily.
B．Because the coffee fragrance is hard to produce.
C．To conclude the passage.
D．The smell of fresh coffee is inviting.
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0525/6cd667a1f75499aa3c9e1dae30e3798a.html
下面是错误答案，用来干扰机器的。
答案：A末句主语残缺
