Logical Reasoning

PT111 · S4 · Q22 Multiple sclerosis is an autoimmune

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Multiple sclerosis is an autoimmune disease: white blood cells attack the myelin sheath that protects nerve fibers in the spinal cord and brain.

Experiment

They tested gamma interferon on MS patients, because they thought that attacks of MS were being triggered by chronic viral infections, and gamma interferon is an ant

(So that must mean that gamma interferon is good at preventing chronic viral infections or eliminating)

Results

All the MS patients became dramatically worse.

Evaluate

Is there something we can infer from the results of the experiment? What does it mean that gamma interferon made MS worse?

Does that mean that MS isn't triggered by chronic viral infections?

Goal

The most available inference seems to be that MS isn't triggered by chronic viral infections. If it were, then gamma interferon would have worked.

Ultimately, we'll pick whichever answer seems to go against the passage the most.

22.

Which one of the following is LEAST compatible with the results of the gamma interferon experiment?

Correct
Gamma interferon stops white blood
Why this is right
What did the passage say about white blood cells / myelin-destroying compounds? It says in the first sentence that MS is a disease in which white blood cells attack the myelin sheath that protects nerve fibers. If gamma interferon stopped white blood cells from attacking the myelin sheath, then that's essentially code language for the idea that "gamma interferon stops MS". But the results of the study are incompatible with that, since giving MS patients gamma interferon made their MS worse.
Skill tested: Must be False · how this choice captures the argument's function is the move to repeat next time.
74% picked this
Administering gamma interferon to those
Compatible Out of Scope
Compatible Out of Scope: people w/o MS The whole paragraph is only about people with MS, so we don't have any ammunition for contradicting some idea about people who don't have MS. This answer would actually fit the overall narrative pretty well, as it turns out. Since MS involves white blood cells doing the damage, then giving someone gamma interferon (which increases white blood cells) should theoretically increase the damage from MS. And that's just what happened! We gave MS patients gamma and the MS got worse.
10% picked this
Medical researchers have discovered that
Compatible
This answer seems to align with the results of the study. In the study, the addition of gamma interferon to the body was correlated with MS becoming much worse. In this answer, the presence of gamma interferon is correlated with MS attacks.
6% picked this
It has now been established
Compatible
This actually seems to match the inference we made, so it fits nicely with the passage. The results seemed to suggest that scientists were wrong in their initial guess: looks like MS isn't triggered by chronic viral infections. This answer reinforces that inference.
6% picked this
The drug now used to
Compatible
This makes a lot of sense. Since more gamma interferon made MS worse, it would stand to reason that less gamma interferon would make MS better. Thus, it makes sense that a drug that lowers gamma interferon activity might also reduce MS attacks.
5% picked this

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