Logical Reasoning

PT107 · S1 · Q11 Of the following, which one most

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It is well known that many species adapt to their environment, but it is usually assumed that only the most highly evolved species alter their environment in ways that aid their own survival.

Opposing Idea

It is usually assumed that only the most highly evolved species alter their environment in ways that aid their own survival.

Main Conclusion

This characteristic — altering the environment to aid survival — is actually quite common (i.e., not limited to the most highly evolved species).

Evidence

The plankton example: plankton emit a gas that helps form sulfate particles, which seed clouds, which reflect sunlight, which keeps the surface cooler — and that cooler surface benefits the plankton.

Evaluate

The plankton story is offered as evidence for the main claim. The claim itself is that environment-altering for survival is widespread — not limited to highly evolved species — which is what the conclusion sentence ("this characteristic is actually quite common") asserts in context.

Goal

Find an answer that says: improving survival by altering the environment is not limited to the most highly evolved species.

11.

Of the following, which one most accurately expresses the main point of the argument?

The Earth would be far
Inference Bait
This is a possible inference from the plankton facts but it's not the main conclusion. The argument's main point is the broad claim that environment-altering is common — not the specific consequence about Earth's temperature if plankton went extinct. The plankton trivia is supporting evidence, not the takeaway.
1% picked this
By altering their environment in
Inference Bait
The argument doesn't conclude that plankton benefit the Earth as a whole — it concludes that plankton benefit themselves by altering the environment, and uses this as evidence that environment-altering for survival is common. Whether the rest of the planet benefits is not the point. This answer also narrows the conclusion to one species (plankton), but the actual conclusion is broader.
10% picked this
Correct
Improving their own chances of
Why this is right
This restates the main conclusion. The author opens by noting an assumption that only the most highly evolved species do environment-altering for survival, then says "this characteristic is actually quite common" — meaning it is not limited to the most highly evolved. The plankton example then supports that broad claim. (C) captures exactly what the argument is concluding.
Skill tested: Main Conclusion · how this choice captures the argument's function is the move to repeat next time.
87% picked this
The extent of the cloud
Premise
This restates a premise from the plankton example — that the formation of clouds over the ocean largely depends on the presence of these particles (which trace back to plankton). It's used as evidence to support the main conclusion, not the conclusion itself.
0% picked this
Species such as plankton alter
Out of Scope
The argument never compares simple species' environmental alterations to the alterations made by highly evolved species in terms of harm to other species. The author's focus is whether environment-altering for survival is widespread — not whether it's more or less harmful when done by simpler species.
2% picked this

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