The question asks us to attack "the store owner's reasoning", but the question tells us nothing about the owner's reasoning. It tells us only:
• from immediate sales alone, the store loses money on Sunday
• the owner wants to close on Sunday
but it never says that the sales figures are the reason the store owner wants to close shop on Sunday. He might just want a day off.
So I don't like the wording of the question, because it's asking us to be psychic and guess at the "owner's reasoning". But if we assume the owner is closing on Sunday because it seems unprofitable to remain open that day, then we're looking for an answer which might explain why it could be profitable to remain open on Sunday, even if the immediate sales figures do not appear to justify remaining open. Only answer A does that.
I don't like the wording of answer B, which says "The electronics store generates less profit on Mondays than on Sundays." We already know from the stem that the store takes a loss on Sundays, but this answer choice suggests it makes a profit on Sundays. Regardless, answer B is not a good answer. Answer B is a justification for also closing on Mondays, not for remaining open on Sundays.
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