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Break the argument into its conclusion and evidence, then do exactly what the question stem asks with that structure.
Answers that sound relevant to the topic but don't connect to the argument's actual reasoning.
Predict what a right answer must do, then test each choice against the conclusion-evidence gap.
Which one of the following, if true, most helps to explain the relative amounts of plaque buildup found in the three groups?
The buildup of plaque on
7% picked this
The stiffness of the bristles
Why this is right
Answer B is correct.
Skill tested: Paradox · how this choice captures the argument's function is the move to repeat next time.
91% picked this
The people who did the
0% picked this
Before they joined the study,
2% picked this
The people in Group 2
0% picked this
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