When a resource's price reflects its full cost to society, consumers pay directly for externalities—the unintended but harmful consequences to society of using a resource. Further, the price of a resource deters misuse of that resource only if it reflects the resource's externalities. So, since sound management of a resource requires that whatever unintended harm to the environment the use of that resource causes.
What this question is testing
Your task
Find the assumption that, if added, guarantees the conclusion follows.
Common trap
Answers that only partly bridge the gap, leaving the conclusion unproven.
Winning move
Identify the new term in the conclusion and pick the choice that links it to the evidence.
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