Logical Reasoning

PT13 · S4 · Q23 A certain species of bird

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A certain species of bird has two basic varieties: crested and noncrested.

Conclusion

The birds' preference for crested or noncrested mates is learned, not genetically determined.

Evidence

The birds normally select mates of their own variety. But a bird raised in an all-crested flock — whether crested or noncrested itself — is later likely to select a crested mate when moved to a mixed flock.

Evaluate

The evidence suggests upbringing shapes preference, but a defender of the genetic view could push back: maybe the noncrested bird raised among crested birds always preferred crested mates genetically anyway, or maybe being raised in a mixed flock would still produce a same-variety preference. To strengthen, we need evidence that further isolates upbringing as the cause and rules out genetics.

Goal

Find an answer that adds another scenario where the bird's rearing environment — not genetics — determines its mate preference.

23.

Which one of the following, if true, provides the most support for the argument?

Birds of other species also
Out of Scope
The argument is about whether mate preferences in this species are learned vs. genetic. Whether birds of other species show preferences for various physical features tells us nothing about the learned-vs-genetic question for this species.
3% picked this
In general there are few
No Impact
The argument is specifically about mate preference. Other behavioral differences between crested and noncrested birds — or the absence of them — don't bear on whether mate preference itself is learned or genetic.
6% picked this
Both the crested and noncrested
No Impact
This is about a different mate-selection trait — size and age, not crest. The argument is about whether crest preference is learned. Whether birds also pick mates of similar size or age says nothing about whether the crest preference itself is genetic or learned.
3% picked this
If a crested bird of
No Impact
This essentially restates evidence already in the stimulus — a bird raised among only crested birds picks a crested mate. The added wrinkle of being "raised in captivity apart from other birds" doesn't change the fact that the bird's only social exposure was crested birds. We already knew that scenario produces a crested preference; it doesn't add new support.
18% picked this
Correct
If a bird of the
Why this is right
This is the strongest possible support. If preference were genetic, a crested bird raised in a mixed flock would still genetically prefer crested mates, and a noncrested bird raised in a mixed flock would still prefer noncrested mates. But the answer says these birds show no preference at all. That fits the learned-preference theory exactly — without a clear "type" to imprint on, the bird doesn't form a preference. It also rules out the genetic theory, since genes would still produce a same-variety preference regardless of flock makeup.
Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.
70% picked this

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