Commentator: The theory of trade retaliation states that countries closed out of any of another country's markets should close some of their own markets to the other country in order to pressure the other country to reopen its markets. If every country acted according to this theory, no country would trade with any other.
The commentator's argument relies on which of the following assumptions?
(A) No country actually acts according to the theory of trade retaliation.
(B) No country should block any of its markets to foreign trade.
(C) Trade disputes should be settled by international tribunal.
(D) For any two countries, at least one has some market closed to the other.
(E) Countries close their markets to foreigners to protect domestic producers.
题目分析：原文建议应该关闭一些外面开的市场让当地自己开，如果这么干了则国家之间就没有贸易了。问假设，A说要是没有贸易必须假设没有国家按照这个理论做，可是原文说如果按照这理论才会没有贸易，反了，不可能是假设，杀。B说要是没有贸易必须假设没有国家会阻止它的市场进行对外贸易，原文谈的是如果按照这理论来会怎么样的一个预测，不是国家应该会怎么干，应该这么干和这么干了是两回事，不可能是假设。C说必须假设贸易争端可以通过国际仲裁来解决，扯得很远，杀。D说要是没有贸易必须假设任何两个国家之间的市场会比较近，比较通顺，留着。E说必须假设国家关闭市场是为了保护国内生产者，扯得很远，杀。
