GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - X5Y7Q24640B65YUJJ

The author of the passage mentions the "inner solar system" in the course of A. explaining how Mars may have acquired a global magnetic field B. explaining how scientists estimate the probable age of Mars C. accounting for the size and location of magnetized patches of terrain detected on Mars D. casting doubt on one possible explanation for the disappearance of a global magnetic field on Mars E. relating how features of the surfaces with large impacts from some chunks of debris.