题型分类：文章总结题
题干分析：选择概括性的正确选项。
选项分析：
B选项：KT期的灭绝摧毁了恐龙等生物，但带来了哺乳动物和一些植物的繁盛。为第二段的概括，正确。
E选项：提出了KT灭绝是陨石撞击导致的气候变化产生的。是对第四段上半段的概括，正确。
F选项：Iridium的浓度和Y半岛进一步证实了陨石假说。是对第四段后半段的概括，正确。

A选项：和第一段中”Collectively, more species went extinct during smaller events that were less dramatic but more frequent.“ 内容相悖。原文是说小规模的灭绝消失的物种更多。
C选项：和第三段中“Nevertheless, climatic explanations for the K-T extinction are not really challenged by the idea that dinosaurs may have been endothermic, because even endotherms can be affected by a significant change in the climate.” 内容相悖。
D选项：恐龙的K-T灭绝是唯一一个被陨石撞击解释的大规模灭绝事件。属于无中生有，跟文章主旨也无关。