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Sara definitely doesn't have a strep infection.
Michael definitely doesn't have strep, and Sara probably has the same illness as Michael.
It seems like the conclusion is too sure of itself. The argument would be valid if it just concluded, .
Look for an answer saying that the other loses track of the distinction between Probably and Definitely
The reasoning in the argument is flawed because the argument
presupposes what it sets out
When an answer says the the premise restated or presumed the truth of the conclusion, it's referring to the famous Circular Reasoning flaw (which is wrong 99% of the time we see it). A circular argument would sound like "Sara definitely doesn't have strep. She might have any number of conditions, but there's no way strep is one of them." Circular Arguments have no evidence. This argument has distinct premises about Michael, his illness, and the connection to Sara's illness.
9% picked this
mistakes the cause of a
This answer is always wrong. It relates to the famous Causal Flaw, in which an author overconfidently interprets something as one specific causal relationship, when other possible explanations exist. When we're pointing out the possibility of other explanations, our wording should sound tentative, like "fails to consider that the purported cause might actually be the result of the purported effect". It's always wrong to say to the author, "WE know what it REALLY is. You mistook cause for effect."
7% picked this
fails to distinguish between acute
The problem with the argument wasn't a failure to consider acute vs. less severe strep. It was just going from saying "Sara probably has what Michael has", to "Sara definitely doesn't have strep".
1% picked this
treats evidence that the conclusion
Why this is right
Given that Michael doesn't have strep and that Sara probably has what Michael has, we can validly conclude that Sara probably doesn't have strep. But the author treated the evidence as though we could conclude that Sara definitely doesn't have strep.
Skill tested: Flaw · how this choice captures the argument's function is the move to repeat next time.
80% picked this
makes a general claim based
This describes the famous Sampling Flaw, and it seems like it fell off a truck and landed here in Q1. Does the conclusion make a general claim? Not at all; it makes a very specific claim about Sara's illness. Is the evidence about particular unrepresentative exemplars of a group? Not at all; it is just about Michael.
4% picked this
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