Since anyone who makes an agreement has an obligation to fulfill the terms of that agreement, it follows that anyone who is obligated to perform an action has agreed to perform that action. Hence, saying that one has a legal obligation to perform a given action required to fulfill one's agreement to perform that action.
What this question is testing
Your task
Describe the reasoning error the argument actually commits.
Common trap
Answers that name a real logical flaw the argument doesn't actually make.
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Articulate the gap in the reasoning yourself, then match it to the choice that describes that gap.
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