- Tue Jun 12, 2018 6:39 pm
#46565
Hey All,
Let me try to address the questions raised here on this somewhat unusual question. This is a question where the Assumption Negation Technique is going to be really important to determining our answer. Let me start with why (B) is the credited answer, and then move on to why (D) is not credited.
Answer choice (B) reads: "The archaeologist’s argument depends on the assumption that the copper tools that were found were present in the region 5,000 years ago." The logical negation of this statement would read: "The archaeologist’s argument depends on the assumption that the copper tools that were found were NOT present in the region 5,000 years ago." If this were true, it would severely weaken the argument - it would mean, basically, that although the tools are 5,000 years old and were found in this region of Canada, they weren't used in this region 5,000 years ago. Perhaps, for example, they were used elsewhere 5,000 years ago and then taken to Canada where they were subsequently found. Were this to be the case, it would certainly weaken the conclusion that the Aboriginal people in Canada built birchbark canoes 5,000 years ago, since the stated tools wouldn't have even have been present for those people at that time.
By contrast, answer choice (D) reads: "The archaeologist’s argument depends on the assumption that the copper tools that were found were the only kind of tool that would have been used for canoe making 5,000 years ago." The logical negation of (D) would therefore read: "The archaeologist’s argument depends on the assumption that the copper tools that were found were NOT the only kind of tool that would have been used for canoe making 5,000 years ago." Would this weaken the conclusion? No, because even if these copper tools were not the only kinds of tools that would have been used for toolmaking 5,000 years ago, that doesn't impact their likelihood one way or the other over whether they were used at all. In other words, copper tools could have been used whether they were the only tools used or there were others used as well - and because of that, the author doesn't need to assume that copper tools were the only type of tools for canoe making to make her argument.
Hope that helps!
Alex