GRE Reading Comprehension: JiJing 352-GRE阅读机经352篇 - CE744GB054GKOIN3J

It can be inferred that the author of the passage would agree with which of the follow about the origin of UHECRs that reach Earth? A. The origin is something other than supernovas in the Milky Way. B. The origin is most likely something other than very distant quasars or gamma-ray bursts. C. The origin is most likely no more than a little over 100 million light-years away from Earth.