The correct answer is: [A]: "You can get cash-back rewards."
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Choice [B]: is incorrect; sometimes you do have to pay sales tax on applicable items; even when using a credit card to make purchases.
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Choice [C]: is incorrect in the sense in that it not the best answer; doing so (mail-in-rebates by mailing receipts ARE NOT EXCLUSIVE to paying with a credit card —this can be done with debit cards; cash payments; etc.
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