Question

in sentence 8 (reproduced below), the writer wants to limit the scope of the claim expressed in the sentence so that it is consistent with the main argument of the passage.
the problem with most probiotic supplements is that no significant clinical trials have proven that they offer demonstrable benefits to the general public.
which of the following changes to sentence 8 best accomplishes this goal?
a changing “problem” to “issue”
b changing “proven that they” to “been confirmed to”
c adding “that can be observed clearly” after “benefits”
d changing “the general public” to “people without gastrointestinal disorders”

Explanation:

The passage's main argument is that probiotic supplements have proven benefits only for specific groups (those with gastrointestinal issues, people on antibiotics, etc.), and unproven benefits for people without these disorders. Sentence 8 currently claims probiotics offer no proven benefits to the general public; to limit the scope and align with the main argument, we need to narrow "the general public" to the group the passage says lacks proven benefits: people without gastrointestinal disorders. Option A and B do not narrow the scope to the relevant group, and Option C adds irrelevant clarity that doesn't align with the core argument of targeted benefits.

Answer:

D. Changing "the general public" to "people without gastrointestinal disorders"