点我领取
免费课程
在线咨询
Positing an enormous volcanic explosion at the end of the Permian period would explain the presence of a buried crater, account for the presence of the element iridium (originating deep within the earth), and the presence of quartz having been shattered by high-impact shock waves.
答案:B
问题:求老师解答一下,B选项直接加of是什么意思。我错选了A,因为感觉也挺对称的 查看答疑

扫我提问哦!