A person’s dietary consumption

Answer choices

1. A

   Out of Scope: lowering threshold8% picked this

   The threshold can be lowered by lowering the dietary consumption of

   We have no evidence that the threshold can be raised or lowered. From the context, it seems like a fixed value.

   8%
2. B

   Opposite10% picked this

   People who consume an average North American diet cannot increase their consumption of cholesterol and fat without dramatically

   The paragraph lets us know that if someone consumes an average North American diet, their serum cholesterol is 4 times the level of the threshold when it switches from proportional increases to barely increasing at all. People consuming an average North American diet will see their serum cholesterol levels rise only gradually, even with dramatic increases in consumption.

   10%
3. C

   Correct80% picked this

   People who consume half as much cholesterol and fat as in the average North American diet will not necessarily have half

   Why this is right

   People who are X will not necessarily be Y is very weak, provable wording, because you can prove such a claim with just one data point: someone who is X, but isn't Y Do we have reason to think that there's someone whose cholesterol and fat intake is 1/2 of the North American diet will not have half as high a serum cholesterol level? Yes! Let's say that the average consumption level of cholesterol and fat in a North American diet is 100 units. The threshold where our serum cholesterol switches from proportional increase to barely increasing is at 1/4 that consumption level, so 25 units. As someone goes from eating 1 unit of cholesterol and fat to eating 25 units, their serum cholesterol will rise proportionately. Since their consumption is 25 times as big, their serum cholesterol will be 25 times as high as it was. But now that they've crossed over that threshold, the serum cholesterol stops rising proportionately and begins barely rising at all. As someone goes from consuming 25 units of cholesterol and fat to consuming 100 units, their serum cholesterol will only gradually move up. Maybe it goes from 25 units to 30 units. This answer wants us to compare someone who eats 50 units of cholesterol/fat to someone who eats 100 (the average North American diet). Both of them are going to have around the same level of serum cholesterol. Maybe the 100 unit diet has a serum cholesterol level of 30 units, but the person eating 50 units will still have a serum cholesterol level of something between 25-30. To put more simply, since people eating the North American diet are at the stage where changes in consumption do not have proportional effects ... if they were to suddenly eat 1/2 as much cholesterol and fat (like the hypothetical person in this answer), they would not see their serum cholesterol drop proportionately.

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

   80%
4. D

   Too Strong: cannot be1% picked this

   Serum cholesterol levels cannot be affected by nondietary modifications in behavior, such as exercising more

   The first sentence says that dietary consumption of fat and cholesterol is one of the most important factors determining serum cholesterol, but this answer choice is acting like it said that dietary consumption is the only factor.

   1%
5. E

   Opposite1% picked this

   People who consume less cholesterol and fat than the threshold cannot reduce their

   If you're below the threshold, then you can easily reduce your serum cholesterol levels, because that's where consumption and serum cholesterol move proportionately. Someone who consumes less than the threshold could reduce their fat and cholesterol consumption by 10% and that would reduce their serum cholesterol by 10%.

   1%