In an experiment, two groups

Answer choices

1. A

   Strengthens, if anything8% picked this

   The doses of ginkgo in the diet of the mice in the experiment were significantly higher than the doses that have been

   It would have weakened the plausibility of the author's causal storyline if we had said, "Yo — we didn't give these mice enough ginkgo to get that stress-reducing effect you've heard about in other studies". Thus, being told the mice did get a dose that was plenty sufficient for stress reduction just helps the author's plausibility.

   8%
2. B

   Correct79% picked this

   Neither the mice who received the ginkgo nor the other mice in the experiment exhibited physiological

   Why this is right

   On a first pass, this probably isn't going to seem appealing (unless we noticed the term shift in the premises), but once we get through a first pass, we need to "open them all up again" and look back to the stimulus for some clue about what we're missing. The author's two premises are like this: - we know ginkgo reduces stress - we know lowering very high stress levels improves memory However, if someone isn't already suffering from very high stress, then we don't know if reducing their stress will actually improve their memory. Since this answer is telling us that none of the mice in the experiment had higher-than-normal stress, then none of the mice had very high stress levels. Thus, this answer is hurting the plausibility of the author's storyline, or we could say it's hurting the logical force of his 2nd premise. His 2nd premise is about things with very high stress levels, and since there weren't any of those things in this experiment, that 2nd premise is totally irrelevant. So that means that the author's argument is now just this: Maybe ginkgo didn't help them by directly helping their memory. After all, ginkgo reduces stress. ? ? ? Without that 2nd premise, connecting stress to memory, we'd be like, "I'm sorry, what is your argument?" By making the author's 2nd premise irrelevant, we have definitely weakened the argument.

   Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.

   79%
3. C

   Too Weak7% picked this

   Some chemical substances that reduce stress in mice also at least temporarily

   Correct answers to questions like Strengthen / Weaken / Paradox / Sufficient Assumption almost never use weak language like "some / can / may / might". This answer tells us that there is at least one chemical substance that reduces stress but impair memory. Okay ... is that substance ginkgo? We have no idea. If ginkgo did this, then yes it would hurt the plausibility of the author's storyline, but since we don't know if ginkgo does this, the answer has only the faintest strength of the "mere possibility" that maybe we're talking about ginkgo.

   7%
4. D

   No impact1% picked this

   Scientists have not yet determined which substances in ginkgo are responsible for reducing

   The fact that we haven't solved the causal mechanism behind ginkgo's stress-reduction effects doesn't matter. If we know that ginkgo reduces stress (regardless of how it works its magic), that's all the author cares about for her causal storyline.

   1%
5. E

   No Impact5% picked this

   The mice who received the ginkgo took just as long as the other mice to learn

   This doesn't hurt the author's causal story at all, since she was only believing that ginkgo helped with recall on the 2nd day of attempting the maze. She was never saying that it would help the mice to learn the maze in the first place.

   5%