All the evidence so far gathered fits both Dr. Grippen's theory and Professor Heissman's. However, the predictions that these theories make about the result of the planned experiment cannot both be true. Therefore, the result of this experiment will confirm one of these theories at the expense of the other.

The argument above exhibits an erroneous pattern of reasoning most similar to that exhibited by which one of the following?

(a)Dave and Jane both think they know how to distinguish beech trees from elms, but when they look at trees together they often disagree. Therefor, at least one of them must have an erroneous method.

(b) Although David thinks the tree they saw was a beech, Jane thinks it was an elm. Jane's description of the tree's features is consistent with her opinion, so this description must be inconsistent with David's view.

(c) David and Jane have been equally good at identifying trees so far. But David says this one is an elm, whereas Jane is unsure. Therefore, if this tree turns out to be an elm, we'll know David is better.

(d)David thinks that there are more beeches than elms in this forest. Jane thinks he is wrong. The section of the forest we examined was small, but examination of the whole forest would either confirm David's view or disprove it.

(e) David thinks this tree is a beech. Jane thinks it is an elm. Maria, unlike David or Jane, is expert at tree identification, so when Maria gives her opinion it will verify either David's or Jane's opinion.

OA and OE will follow after the discussion

I am down to C and E, and ultimately will go with E.
In C, conclusion does not confirm one alternative at the expense of other as Jane is unsure. If tree is not elm, then David is wrong but not on expense of Jane.

Choice E correctly states that when Maria gives her opinion, it will verify either David's or Jane's opinion. So this choice confirms one opinion at the expense of other.

Initially I chose B. But later on I realized that C is more apt.
"at the expense of" suggests that both theories are equally good but due to the results one theory will be rejected. Now, C says that Davids theory will be "better" than Jane's and hence Jane's theory will rejected inspite of being "good".

OA is E. The argument proceeds as follows.

The conclusion of the author is that the experiment will confirm one of these theories at the expense of the other. In other words, one will be true whereas the other will be false. The flawed in the argument is that the author does not account for both theories to be false.

Option E contains the same flawed in reasoning. Maria is the experiment and David and Jane the theories.

+ 1 for getmba

I still was not able to get the reasoning behind the answer choice. I thought the answer need to be B.
_________________

Never give up,,,

Ok, now I got it, thank u!
_________________

Never give up,,,

what is the OA and source