There is a conditional relationship in this stimulus,
saiffshaikhh@gmail.com. The last sentence establishes that IF the body hadn't been sealed in the glacier shortly after death, OR IF it had thawed between then and now, THEN it would not be well preserved. But since it was well preserved, we can conclude that it was sealed in the glacier shortly after he died AND that the body did not thaw between then and now. Thus, the glacier stayed frozen for 4000 years or more, from the time the man died until it recently thawed.
This makes C the right answer, not D or E. The glacier has to be that old.
D is incorrect because we have no way of knowing what would have happened to the artifacts if they had thawed. We only know about the body. Maybe one of the artifacts was a knife made out of stone that would have been unaffected by thawing?
E is incorrect because we know nothing about the global climate from these facts. The glacier may be thawing, but other parts of the planet might be getting colder, and the average could be going up, down, or staying the same. Answer E is just speculation that goes way beyond the limit of what the stimulus can tell us.
Adam M. Tyson
PowerScore LSAT, GRE, ACT and SAT Instructor
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