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this question asks us which one of the following is true most strengthens the argument so we're looking at a strengthened question that means that the answer will help the argument in other words it will make the conclusion more likely to follow from the given support if we assume the answer to be true the for wrong choices will either weaken the argument or do nothing to the argument if we assume them to be true pause the video now if you'd like to try this question on your own otherwise let's move on to the explanation okay let's read this stimulus and for strengthen questions it helps to read actively for the conclusion and the support since the connection between those two parts is what we'll be looking to strengthen the passage reads a recently completed study of several hundred subjects all of approximately the same age showed that those who exercised regularly during the study were much less likely to die during the study this indicates that exercise can actually increase one's lifespan okay is the first sentence our support or our conclusion it's pretty safe for us to identify it as support since it involves a study a study is just something that took place and gave certain results and here those results are that people who exercised regularly during the study were much less likely to die during the study now it's the interpretation of the study that often lends itself to subjectivity and that's what we have in the second sentence with the really good signal word indicates the arguer is interpreting the study's result to mean that exercise can increase one's lifespan so we can mark that as our conclusion okay for strengthen questions it's usually the case that there are lots of different specific ways to strengthen the argument and all of those ways are completely legitimate so a specific prediction isn't necessary or even usually recommended sometimes though you might see a familiar pattern on test day like a certain structure that you've seen a lot of in your practice and here we see a study when you see a study in logical reasoning it can be a good idea to examine the potential holes in the study we do learn that these subjects here are approximately the same age so that gives us one point of fairness about the study however we're only given a correlation and that correlation is that the people who exercised regularly were the same people who were the least likely to die then what happens is we shift to causation in the conclusion the argue believes that one of the correlated attributes causes the other so it's possible that a strengthener will address this gap and Bridget so that the causation is more likely to be true based on the correlation that the study shows so to rephrase our task we're looking for something that makes it more likely that the study is connected to real life great now that we know what we're trying to accomplish let's evaluate the choices a the subjects who did not exercise regularly during the study tended to have diets that were more unhealthy this information actually weakens the argument it's bringing up something else that could have caused the difference in death rates like it's possible that it wasn't more exercise that helped people die less but rather it was healthier diets so choice a presents an alternative cause and that weakens the causal relationship that the arguer believes to exist be the subjects who did not exercise regularly during the study tended to blame their lack of exercise on a lack of time this information doesn't affect the argument at all we aren't interested in what the subjects blame for their lack of exercise we're interested in whether their lack of exercise effective their likelihood of death it doesn't matter that the subjects claim to not have enough time see a large number of the deaths recorded were attributable to a pre-existing conditions or illnesses this is a lot like choice a because it weakens the argument by giving a different reason that people could have died during the study maybe it wasn't lack of exercise that did it but rather maybe the people who didn't exercise regularly were already unhealthier than the people who did exercise regularly for example so this is a weakened er D whether or not a given subject was to exercise during the study was determined by the researchers on a random basis this is our strengthener this choice directly strengthens the connection of the study to the conclusion because it removes the possibility that people who didn't exercise did so for specific health related reasons another if their researchers randomly selected who exercised and who didn't then that random sampling makes the study more representative if a choice removes a potential weakened er like this choice does then the overall effect is that it strengthens the argument because it takes away one possibility that would have hurt the argument if it were true for the record choice II states a person who exercises regularly is probably doing so out of concern for his or her own health this doesn't strengthen the argument a person's motivations don't affect this argument because people could have very different motivations for exercising but the fact remains that they exercise and we need to know whether that exercise whatever the motivation for it is increases one's lifespan so to recap for strengthened questions you're finding the choice that helps the link between the evidence and the conclusion it really helps to separate the evidence and the conclusion by seeing the evidence as information that we're given and then seeing the conclusion as an opinion that the arguer makes based on that information well in a strengthened question we want to bring the two pieces closer together we want to make it more likely for the conclusion to happen based on the evidence that was provided it can also help to pretend that you are adding each choice to the argument and seeing which way the argument moves in quality does it get better does it get worse does it stay the same look for any gaps in the argument like where the evidence is addressing one thing and the conclusion that addresses a different thing and then look for a choice that helps close that gap or sometimes you can also strengthen an argument by removing a potential weaken er like we did in this question keep a good grasp on the structure of the argument and what you're being asked to accomplish