However wealthy we may be, we can never find enough hours in the day to do everything we want. Economics deals with this problem through the concept of opportunity cost, which simply refers to whether someone’s time or money could be better spent on something else.

Every hour of our time has a value. For every hour we work at one job we could quite easily be doing another, or be sleeping or watching a film. Each of these options has a different opportunity cost—namely, what they cost us in missed opportunities.

Say you intend to watch a football match but the tickets are expensive and it will take you a couple of hours to get to and from the stadium. Why not, you might reason, watch the game from home and use the leftover money and time to have dinner with friends? This--- the alternative use of your cash and time – is the opportunity cost.

…

59. The “leftover… time” in Paragraph 3 probably refers to the time _________.

A. spared for watching the match at home

B. taken to have dinner with friends

C. spent on the way to and from the match

D. saved from not going to watch the match

老师们好。这个题官方答案是C。我的疑问是：

   leftover…time真的是指“the time spent on the way to and from the match”（已经花在往返比赛路上的时间）吗？

 既然time已经spenT在路上了，还谈什么leftover time呢？ 花了之后，不是就没有了吗?

请老师指点迷津。谢谢。