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Find the assumption the argument requires in order for its conclusion to hold.
Answers that would help the argument but aren't strictly required (sufficient, not necessary).
Negate each choice — the right one breaks the argument when negated.
The argument that the direction of the Earth’s magnetic field has changed over time requires the assumption that
only lava can be used
7% picked this
a single volcano can produce
10% picked this
not all solidified lava has
Why this is right
Answer C is correct.
Skill tested: Necessary Assumption · how this choice captures the argument's function is the move to repeat next time.
81% picked this
there are fewer volcanic eruptions
0% picked this
as lava flows down the
3% picked this
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