sec13-16谢谢！！

For a trade embargo against a particular country to succeed, a high degree of both international accord and ability to prevent goods from entering or leaving that country must be sustained. A total blockade of Patria’s ports is necessary to an embargo, but such an action would be likely to cause international discord over the embargo.

The claims above, if true, most strongly support which of the following conclusions?

(A) The balance of opinion is likely to favor Patria in the event of a blockade.

(B) As long as international opinion is unanimously against Patria, a trade embargo is likely to succeed.

(C) A naval blockade of Patria’s ports would ensure that no goods enter or leave Patria.

(D) Any trade embargo against Patria would be likely to fail at some time.（D）

(E) For a blockade of Patria’s ports to be successful, international opinion must be unanimous.

不太明白Ｅ为什么不对．

根据这一句：For a trade embargo against a particular country to succeed, a high degree of both international accord and ability to prevent goods from entering or leaving that country must be sustained　Ｅ不对吗？both...and....这个两都必须满足，embargo才成功．Ｅ说了其中一个必须满足，是个子集，也对呀．

我的思路错在哪里？　谢谢

unanimous: (of a decision, statement, etc) supported or agreed by everyone.

however, the requirement in the stimulus in only high degree agreement.