Amy is thinking about going to the movies tonight. A movie ticket costs $15, and she’ll have to cancel a $20 dog-sitting job that she would have been willing to do for free. The opportunity to Amy cost of going to the movies is:

Amy is thinking about going to the movies tonight. A movie ticket costs $15, and she’ll have to cancel a $20 dog-sitting job that she would have been willing to do for free. The opportunity to Amy cost of going to the movies is:
A.$35.
B.$5.
C.$20.
D.$15.
正确答案：$35.