Answer:
credit card with an APR of 18 percent with a grace period of twenty-five days
Explanation:
As all of the options have a minimum APR, annual percentage rate, of 18 the best option that she can find is the one with the credit card that has the same 18 APR but a period of grace of 25 days, this means that if she pays the full amount in the first 25 days after his purchase she wont have to pay any interests.