题目

Science has told us so much about the moon that it is fairly easy to imagine what it would be like to get there. It is certainly not a friendly place. Since there is no air or water, there can be no life of any kind. There is not much variety of scenery cither. For mile after mile there are only flat plains of dust with mountains around them. Above, the sun and stars shine in the black sky. If you step out of the mountain shadow, it means moving from the severe cold into intense(强烈的)heat. These extreme temperatures continually break rocks away from the surface of the mountains. The moon 如果导函数图像的顶点坐标为，那么曲线上任一点的切线的倾斜角的取值范围是（   ）A． B． C． D．