Answer:
A. person buys something with a marginal benefit more than what they paid.
Step-by-step explanation:
Consumer surplus occurs when the price a consumer is willing to pay for a product is higher than the market price. For example if a customer is willing to pay $10 for a book, but the sale price is $8 the consumer surplus is $2.
Since the consumer perceives he paid less than the value of the good, the marginal benefit he enjoys is more than the price paid.