The correct answer is C. Thrifty
Explanation:
In the sentence "Ashley thought her parents were being cheap when they bought generic headache medicine, but it worked as well as the name brand.", the word cheap means Ashley believe her parents were not generous for buying a generic medicine, but admits even though the medicine was generic it worked as well as the name brand, this implies the decision of buying the generic medicine was a positive one as Ashley parents save some money. This implies the word "cheap" in this context aims at showing Alison parent are careful when spending money and thus are "thrifty" persons, this means they try to save money while buying the products they require, which is different from "frugal" as frugal persons avoid buying certain products to save money. Thus, in this sentence, the word "cheap" is a synonym of "thrifty" as it denotes Ashley parents try to save money by buying cheaper but effective versions of the same product.
