Solve clearly

Thomas has a ticket to go to a movie this Saturday. He was willing to pay $20, but he only paid $15 for it. After he bought the movie ticket his friend offered to take him out to dinner Saturday evening. Thomas has to choose between going for the movie or a free dinner. He can resell the ticket for $10. What is the lowest value that Thomas should place on the free dinner to make him choose the free dinner rather than the movie? Select an answer and submit. For keyboard navigation, use the up/down arrow keys to select an answer. a $20 b $15 C $10 d $5