The question stem reads: The flawed pattern of reasoning in which one of the following is most closely parallel to that in the argument above? This is a Parallel Flaw question.

The author states," A species in which mutations frequently occur will develop new evolutionary adaptations in each generation." We can translate this into lawgic to read:

Mutations Frequently Occur -> Develop Evolutionary Adaptations

The author then states the premise and conclusion, "Since species survive dramatic environmental changes only if they develop new evolutionary adaptions (premise), a species in which mutations occur frequently occur will survive drastic environmental changes (conclusion)." Let's translate those into lawgic:

Premise:
Survive Dramatic Environmental Changes -> Develop Evolutionary Adaptations

Conclusion:
Mutations Frequently Occur -> Survive Dramatic Environmental Changes.

We can combine the argument to read:

P1: Mutations Frequently Occur -> Develop Evolutionary Adaptations
P2: Survive Dramatic Environmental Changes -> Develop Evolutionary Adaptations
____________________________________________________________________________
C: Mutations Frequently Occur -> Survive Dramatic Environmental Changes

We can see that the author confused the sufficient and necessary conditions of P2. Evolutionary adaptations are a requirement to survive dramatic environmental changes, but there might be additional requirements, such as having enough food. Let's take the general form of the argument:

A -> C
B -> C
____________
A -> B

By that line of reasoning, we could conclude that all apples (A) are peaches (B) because all apples (A) are fruit (C), and all peaches (B) are fruit (C).

When evaluating an answer choice, we need two sufficient conditions pointing to the same necessary condition. We also need a conclusion that says one of those sufficient conditions is sufficient for the other sufficient condition. Now that we know what we are looking for let's turn to the answer choices.

Answer Choice (A) is incorrect. The first premise says: properly built -> stones support each other. So the next premise needs "stones supporting each other" for the necessary condition. However, we get: sturdy -> properly built. So we can stop reading there.

Answer Choice (B) is incorrect. The first premise says: play before a different audience -> never get the same reaction. So the next premise needs to have "never get the same reaction" for the necessary condition. However, we get: play -> always has a different audience. Like (A), we can stop reading there.

Correct Answer Choice (C) is what we discussed. The first premise says: perfectly honest -> always tell the truth. So the next premise needs "always tell the truth" in the necessary condition. The next premise says: morally upright -> always tell the truth. Ok, so that checks out. The conclusion has to say: perfectly honest -> morally upright, which is exactly what (C) says. So (C) is the right answer.

Answer Choice (D) is incorrect. The first premise says: garden productive -> soil well drained. So the next premise needs "soil well drained" in the necessary condition. However, we get: soil well drained -> good soil. So we can eliminate (D).

Answer Choice (E) is incorrect. The forest premise says: diet healthful -> well balanced. So the next premise needs to have "well balanced" in the necessary condition. However, the next premise says: well-balanced -> includes fruit and vegetables. So we can eliminate (E).


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Clark: Our local community theater often produces plays by critically acclaimed playwrights. In fact, the production director says that critical acclaim is one of the main factors considered in the selection of plays to perform. So, since my neighbor Michaela’s new play will be performed by the theater this season, she must be a critically acclaimed playwright.

Summarize Argument
Clark concludes that Michaela must be a critically acclaimed playwright because her play is being featured at a local theater that values critical acclaim and often performs plays by such people.

Identify and Describe Flaw
The problem with this argument is that Clark never establishes that every play performed by the theater is written by a critically acclaimed playwright. He would need to establish this in order to conclude that Michaela, by virtue of her work being performed there, is definitely critically acclaimed. Evidence that critical acclaim is one of the main factors considered by the theater is not enough to establish it as a necessary condition, since the theater may also perform many plays by writers without critical acclaim.

A
takes a condition necessary for a playwright’s being critically acclaimed to be a condition sufficient for a playwright’s being critically acclaimed
Clark doesn’t say that a playwright having their work performed by the theater is necessary for being critically acclaimed; he only mistakenly assumes that it’s sufficient to prove it.
B
fails to consider that several different effects may be produced by a single cause
The argument never mentions any cause-and-effect relationship. The flaw is assuming that someone’s work being performed by the theater is sufficient to prove that they’re critically acclaimed.
C
treats one main factor considered in the selection of plays to perform as though it were a condition that must be met in order for a play to be selected
This describes how Clark assumes that critical acclaim is a necessary condition for having one’s play performed at the theater. Since it’s not actually established as necessary, there could be many plays performed that aren’t critically acclaimed.
D
uses as evidence a source that there is reason to believe is unreliable
The only source Clark appeals to is the production director, and there’s no reason to believe that this source is unreliable.
E
provides no evidence that a playwright’s being critically acclaimed is the result rather than the cause of his or her plays being selected for production
Clark doesn’t claim that critical acclaim results from one’s play being chosen by the theater, so there’s no need to provide evidence for it.

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