Logical Reasoning

PT142 · S1 · Q15 Researcher: Salmonella bacteria are

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Researcher: Salmonella bacteria are a major cause of illness in humans who consume poultry.

Given that ..

The chicks who underwent the Salmonella treatment had a lower rate of the Salmonella bacterial infection.

Why is it that ...

One week after treatment, treated chicks had higher concentrations of a variety of bacteria than the untreated chicks did?

Anticipate

This one might not read as obviously paradoxical at first, but the tension seems to be that Salmonella is a bacteria, so presumably the treatment the young chicks got was some sort of anti-bacterial treatment.

If the treatment is successfully keeping Salmonella bacteria at bay (preventing infection), how are other types of bacteria flourishing more than usual?

Goal

We need an answer that provides a distinction about the chicks who got the Salmonella treatment. It will probably relate to the treatment itself and show how suppressing the Salmonella bacteria indirectly leads to the flourishing of other types of bacteria (maybe they're in competition with each other, so limiting one allows the other to multiply).

15.

Which one of the following, if true, most helps to explain the concentrations of bacteria one week after the treatment?

  1. The new treatment takes several

    No Distinction

    The puzzling fact we're here to explain takes place one week after the treatment was administered. This is just talking about how long the treatment took to administer. Whether it took two days or three weeks to administer, we're trying to figure out why, one week later, the chicks had higher levels of other bacteria. This gives us no way to explain that.

    4% picked this

  2. Levels of Salmonella bacteria in

    Cheats Paradox

    This is talking about the levels of Salmonella bacteria, but we need to explain the higher levels of a variety of other bacteria.

    2% picked this

  3. Most chicks develop resistance to

    No Distinction

    This is about any chick, not specifically the treated vs. untreated ones. So this doesn't give us any storyline for how the treatment led to elevated bacteria.

    2% picked this

  4. The untreated chicks experienced a

    Restates Paradox

    This essentially extends the puzzle without explaining it. It makes sense that if the treated chicks have higher levels of other bacteria that these high levels could lead to non-salmonella infections. But we're trying to figure out why they have higher levels of other bacteria in the first place, and this answer provides no storyline for that.

    5% picked this

  5. Correct

    The bacteria found in the

    Why this is right

    This provides a distinction about the treated chicks that would explain their elevated bacterial levels. Other bacteria is normally inhibited / limited / constrained by Salmonella bacteria. So when we give them the treatment that kills off their Salmonella bacteria, it allows these other bacteria to grow / multiply.

    Skill tested: Paradox · how this choice captures the argument's function is the move to repeat next time.

    87% picked this

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