问一道题：NO.PZ2018062003000179

问题如下：

Suppose there are only two countries, Japan exports cloth to South Africa and imports coffee from South Africa.The output per worker per day in each country is as follows:

Which country has a comparative advantage in the production of cloth and what is the most relevant opportunity cost?

选项：

South Africa: 2 cloth per coffee.

Japan: 2 cloth per coffee.

Japan: 1/3 coffee per cloth.

解释：

C is correct.

Although South Africa has absolute advantage in both two fields, Japan has a comparative advantage in the production of cloth. The opportunity cost of cloth in Japan and in South Africa is ⅓ and ½ of the coffee.

考点：比较优势

解析：根据表格，日本生产1单位的布的成本是1/3的咖啡，而南非生产1单位的布的成本是1/2的开啡。所以日本生产布具有更低的机会成本，那么日本就应该生产布，南非则应该生产咖啡。C选项正确。