Hi Noor,
In a general sense, in every argument, the author assumes that his or her premises are sufficient to draw his or her conclusion. In other words, the very broad assumption underlying every argument is that "If my premises are true, then what I've said in my conclusion must be true" (in conditional diagramming terms: Premises
Conclusion). So, yes, it's fair to treat the conclusion of an argument as something the author assumes to be a necessary condition following from the premises. This will have varying levels of application (or even relevance) depending on the nature of the assumption question. But having that background assumption in mind turns out to be especially helpful on many of what PowerScore classifies as "Supporter Assumption" questions (which this one is!).
I hope this helps!
Jeremy
Jeremy Press
LSAT Instructor and law school admissions consultant
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