Sunspots are cooler than the rest of the sun's surface because A.they produce less energy. B.they are buried in the sun. C.they are faraway from magnetic fields. D.they are close to magnetic fields.
A.they B. B.they C. C.they D. D.they
【参考答案】
A 解析:在第二段里这个问题讲得十分具体,这段的最后两句提到,由于黑子发出的光和热相对较少,它们颜色更暗,也比太阳表面的其他部分凉爽。所以A是正确答案。