As the price of both the apartment is the same so the price of apartment B is not the opportunity cost of apartment B. Opportunity cost is what we give up to get another alternative. Here, apartment B is located in green and pollution free locality. But apartment A is located in the polluted and noisy area. So to live in apartment A Olivia has to sacrifice the pollution free environment. Therefore the opportunity cost of choosing apartment A is the green and pollution free locality. Option d is correct.
O Olivia has been looking for a new apartment and finds two apartments that fit her...