Self-study
A study of the dietary habits of a group of people who had recently developed cancer and a group without cancer found that during the previous five years the diets of the two groups' members closely matched each other in the amount of yogurt they contained. ██████ ████████ ██████████ █████ ██ █████████ ██ ███ ████ ██ ██ ███████ ██ ███ ██████ ████ ██████ ███ ██████ ██ ████ ██████ ████ ███ ███ ██ ███████ ███ █████████ ██ ███ ██████ ████ ████ ██████████ ██ ███ ██ █████████ ████ █████████ ██ ███████ █████████ ███ ██████ ███████ ██ ███████ ██ ██ █████████████
Summarize Argument: Phenomenon-Hypothesis
The author hypothesizes that too much galactose in the body causes cancer. She supports this by referring to a study comparing the diets of people with and without cancer. The study found that both groups ate similar amounts of yogurt, which contains galactose. However, people with cancer had low levels of the enzyme needed to process the galactose in the yogurt.
Notable Assumptions
The author assumes that galactose can cause cancer just because people with cancer had low levels of the enzyme needed to process it. She overlooks the possibility that another factor could cause both the cancer and low enzyme levels, or that cancer might lead to low enzyme levels.
In order to conclude that galactose can cause cancer, she also assumes that the study is representative and that all other factors or differences between the two groups are controlled for.
3.
Of the following, which one ███████████ ███ █████████ █████████ ██ ███ █████████ ██ ███ █████████
a
The argument fails ██ ████████ ███████ ███ ███████ ██████ ██ ████████ ██ ███ ███ ██████ ████ ███ ████ ██ ███ █████ █████████
The study should control for other factors and differences between the groups, but it doesn’t need to prove that the dietary habits of everyone in the two groups were the same in all other respects. (A) is too strongly worded to successfully weaken the author’s argument.
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.
b
The argument neglects ██ █████████ ████ ██████ ████ ███ ██████ ██ ███ ██████ █████ ██████ ███████
The author’s conclusion only addresses a potential cause of cancer. She isn’t giving a recommendation for what people should or should not eat. Because (B) doesn’t address causation, it’s not relevant to the author’s argument.
c
The argument focuses ██ ████ ███ █████████ ████ ███ ████████ ███ ████ ██ ███████ ████ ██ ██ ████ █████ ████ █████ ███ ████ ████ ███████████
There are certainly other substances that increase the risk of cancer, but the author is only drawing a conclusion about the presence of galactose and the enzyme needed to process it. She does not need to address every possible carcinogenic substance.
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
The argument overlooks ███ ███████████ ████ ██████ ██████ ███ ██████ ██ ███ ███████
Just because there’s a correlation between cancer and low levels of the enzyme, doesn’t mean that low levels of the enzyme cause cancer, as the author concludes. It’s possible that cancer causes low levels of the enzyme instead.
Alternate explanation
Alternate explanation
Weaken: Introduce or support an alternate explanation for a phenomenon.
Strengthen: Helps to eliminate an alternate explanation for a phenomenon.
e
The argument does ███ ███████ ███████ ███ ██████ ██ ██████ █████ ██████ ███ ██████ █████████
This is true, but it doesn't weaken the argument. The study found that one group had enzyme levels too low to process the galactose they were eating. Even if they still had some amount of the enzyme, the key point is that it wasn’t enough to process the galactose.