At the end of the passage the author suggests that（　）.

题库:综合类 类型:最佳选择题 时间:2017-07-03 03:11:35 免费下载:《单项选择》Word试卷

At the end of the passage the author suggests that（　）.
A.it is impossible for life to exist on other planets.
B.earthlike life could only exist on a few planets.
C.life could exist on only one planet in a million.
D.life could exist on a great number of planets.

本题关键词:肛I,石I鱼,因子I,I因子,I导联,I度烧伤,I类抗原,I期愈合,I类分子,I类环境;