Logical reasoning PrepTest 147 · Section 4 · Question 6

Incorrect. This answer is the negation of the assumption made by the argument, which features animals that have a lot of food and no exercise.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Strengthen with Necessary Premise

Stimulus Summary:
Lab animals have all the food they can eat and don't exercise. Since studies assume that lab animals are healthy, their living conditions can skew the study. Here's an example!

Answer Anticipation:
First, the example here is meant to make the argument easier to follow. If you're having difficulty understanding the first part of the argument, read through the example to help clear it up (though we think the example is actually harder to track than the argument). If you're pretty solid on the argument, use the example to confirm your understanding. In either case, it's almost certainly not going to be relevant to the answer since it backs up the other premises.

And looking at those premises, there's a pretty big gap between them. The first premise establishes that lab animals have lots of food and little exercise. The second then goes on to talk about studies assuming lab animals are healthy—meaning that unhealthy animals would create problems for the studies. Since the conclusion is that the results of studies are skewed, the argument is assuming that the lab animals are unhealthy. And, therefore, the argument is assuming that easy access to food and no exercise will make an animal unhealthy.

Answer Explanation:
This answer connects what we know about the lab animals to the determination that leads to the conclusion. If animals with a lot of food but no exercise can't be unhealthy, then the results wouldn't be skewed by the unhealthy animals and the argument falls apart.

Key Takeaway:
Examples can help to make arguments easier to understand, but they're usually "extra"—pieces of the argument to help the reader but not inherently necessary to the logic. Therefore, for a Strengthen with Necessary Assumption question, they're likely something you can ignore.

Incorrect. The argument doesn't require assuming anything about a different set of animals other than the ones in the lab. Whether wild animals are healthy, unhealthy, full, starving, or in marathon shape is out of scope.

Incorrect. The conclusion is that certain factors can skew results—if anything, studies taking those factors into account would weaken the argument.

Incorrect. As long as the eating habits are unhealthy, it doesn't matter to the argument if the animals have the same daily unhealthy eating habits, or they find new ways to eat unhealthily each day.