Logical Reasoning

PT12 · S1 · Q16 Salmonella is a food‐borne microorganism

A free, expert breakdown of this official LSAT Logical Reasoning question.

Save & drill this skill — build targeted practice sets from questions like this one
Video walkthroughs — watch every question solved step by step
81 official LSATs — as questions, timed sections & full-length tests

Salmonella is a food‐borne microorganism that can cause intestinal illness.

Conclusion (clearly)

Public health officials would be well advised to replace the previous Salmonella tests with the new test.

Evidence

Salmonella is a food-borne microorganism that can cause intestinal illness, which is sometimes fatal, especially if not identified quickly and treated.

Conventional Salmonella tests on food samples are slow and can miss unusual strains of the microorganism.

The new test identifies the presence or absence of Salmonella by the one piece of genetic material common to all strains.

Evaluate

This argument fits the Recommendation pattern. The author is assuming that the upsides of switching to the new test outweigh the downsides.

The author suggests that the upsides are that could be faster and more comprehensive than conventional tests that can be slow and potentially miss unusual strains.

GIVEN these upsides HOW CAN WE ARGUE we should not switch to the new test?

We need to explore if there are potential downsides or issues with the new test.

Goal

Let's find an answer that shows a downside to replacing the old tests with the new test.

16.

Which one of the following, if true, most substantially weakens the argument?

The new test identifies genetic
No Impact
If anything, it sounds like a good thing that the new test is specific to Salmonella. That way similar bacteria won't be giving us false positives. We're looking for something negative about the new test.
16% picked this
Correct
The new test detects the
Why this is right
If the new test detects Salmonella at levels too low to pose a health risk, this undermines the argument. The new test might result in many false alarms, detecting harmless low levels of Salmonella, potentially causing unnecessary panic, misuse of resources, or misguided interventions that offer no real health benefit.
Skill tested: Weaken · how this choice captures the argument's function is the move to repeat next time.
73% picked this
Salmonella is only one of
No Impact
The fact that other illnesses also cause gut problems has nothing to do with us deciding how we should test for Salmonella.
4% picked this
The new test has been
No Impact
We don't care about the backstory leading up to this new test, unless it suggests an upside or downside compared to the current test. If anything, this suggests an upside, since it's made possible by "dramatic advances in science". We want to hear something negative about the new test.
1% picked this
Symptoms of Salmonella poisoning are
No Impact / No Distinction
We're trying to figure out how we should test for Salmonella. The fact that its symptoms can be mistaken for those of other illnesses might lead to false diagnoses if the current test or new test can't tell the difference between Salmonella and these other illnesses. But we have no reason to think that the existence of these similar illnesses would confuse one test more than the other. If anything, we know that the new test would not be confused by what this answer is saying, because the new test has nothing to do with analyzing a person's symptoms. It just involves testing for a piece of genetic material.
6% picked this

Continue the review in LSAT Lab

Save this question, watch the video walkthrough, and drill similar questions in your LSAT Lab account.

Save and practice this skill

LSAT Lab

Turn this review into a targeted study plan.

Save this question, drill more like it, watch the video walkthrough, and track your progress in your LSAT Lab account.

Start practicing free