Self-study
Scientists hypothesize that a particular type of fat known as Conclusion "P-fat" is required for the development of eyesight. ███████████ ████ ███ ██ ████ ██████████ ██ █████████ ████ ██████ ███ ███ ███ ████████ ███ ██ █████ ████ ██ ████ █████ ████████ ████ ██████ ███ ████████ █████ █████ ██ ████ ██ ██████ ██ ███ ████ ████ █████ ████ ██████ ████ ███ ████ ██ ███ █████ █████████ ████ ██ ████ █████ ████████ ████ ██████ ███████ ██ █████
Summarize Argument: Phenomenon-Hypothesis
Scientists hypothesize that P-fat is necessary for developing eyesight. This is because babies fed mother’s milk, which is high in P-fat, typically have better eyesight than babies fed formulas low in P-fat. Moreover, babies born five to six weeks premature usually have worse eyesight than babies carried to term.
Notable Assumptions
The scientists assume that P-fat is the only relevant difference between formulas and mother’s milk. If there was some other difference, then that difference could just as well account for the difference in eyesight.
The scientists also assume that babies carried to term receive more P-fat than those born prematurely; otherwise, this factor would be unconnected to the hypothesis.
14.
Which one of the following, ██ █████ ████ ████████ ███ ███████████ ███████████
a
Adults whose diets ████ █████ ████ ██ ████ █████ ████████ ████ █████ █████ █████ ███ ████ ██ ██████
The hypothesis is specifically about developing eyesight. We don’t have any reason to think that factors in adult eyesight have any relevance to infant development, so this is irrelevant.
b
A fetus typically ████████ ████ ██████ ██ █████ ████ ███ ██████ ██████ ████ ███ ████ ████ █████ ██ ██████████
This explains why we care that premature babies have worse eyesight: there's a link to P-fat levels. This strengthens the causal connection between P-fat and developing eyesight, which supports the hypothesis.
Plausibility
Plausibility
Presenting evidence that corroborates (in Strengthen) or conflicts (in Weaken) with the author's hypothesized explanation or the predictions that follow from that explanation.
c
Babies whose mothers ████ ████ ████████ ██ ███ ████ ██ ████ ████ ████████ ███████████
All this tells us is that eyesight isn’t totally genetic. However, we’re specifically trying to strengthen the connection between P-fat and eyesight. This doesn’t do that for us, so it's irrelevant.
Failed alternate explanation
Failed alternate explanation
Weaken Qs: Answers that try to introduce an alternate explanation, but fall short, or try to explain a different phenomenon.
Strengthen Qs: Answers that try to eliminate an alternate explanation, but fall short, or try to eliminate an explanation for a different phenomenon.
d
Babies generally prefer ████████ ████ ██ ████████ ███ ██ ██████
We don’t care what babies prefer, because we don't know if that has anything to do with how they develop eyesight. Without a more explicit connection, their preferences aren't relevant.
e
The eyesight of █ █████ ████████ ██████ ███ ████ █████████ ██ ██████████
If this means there's no further development after birth, then this weakens the scientists’ hypothesis, because the postnatal difference between formula and mother’s milk wouldn’t be relevant. And we still don't know what role P-fat has in gestation.
Directionally wrong
Directionally wrong
Answers that, if they have any effect, do the opposite of what we want (weaken when we're trying to strengthen, or strengthen when we're trying to weaken).