Yes, there can be two flaws (or more if you count: "the argument fails to take into account everything under the sun." But one of them is the main flaw. And even if you can't determine which one is the main flaw, only one of the answer choices will speak directly to a flaw in the argument.
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Yes, there can be two flaws (or more if you count: "the argument fails to take into account everything under the sun." But one of them is the main flaw. And even if you can't determine which one is the main flaw, only one of the answer choices will speak directly to a flaw in the argument.
What 2ndTimestheCharm said!