一題經濟問題 - 經濟

學校小考的題目

可是想不出是為什麼


Suppose that Martin owns a lighthouse, and Lewis owns a bearby port. Martin's

lighthouse benefits only those ships that enter Lewis's port. Which of the

following statements is "not" correct?


A. Martin's lighthouse may be considered a private good.
B. Martin can reduce the free-rider problem by charging Lewis a usage fee.
C. Martin can exclude Lewis's port form benefiting from the lighthouse by
simply truning the power off.
D. Martin's lighthouse may be considered a common resource.


答案是d

不過我不知道d錯在哪?

我覺得a也是錯的

感覺應該是無法排它 也不具敵對性

想請高手幫忙解答一下

謝謝~





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