Answer:
B. Cooking dinner for some friends.
Step-by-step explanation:
Opportunity cost is the cost of next best alternative sacrifised while choosing an alternative.
Eg- If I like Chapati more than rice, rice more than bread - opportunity cost of chapati is only rice & not bread.
If my preferences are 1 > 2 > 3 ; {'>' implies 'preferred over'}
Then the opportunity cost of my 1st preference i.e going out to movie & dinner is the 2nd best preference i.e Cooking dinner for some friends.
Hamburger at base ball game i.e 3rd preference is opportunity cost of 2nd preference i.e Cooking dinner for some friends.