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? ['The balance of opinion is likely to favor Patria in the event of a blockade.', 'Any trade embargo against Patria would be likely to fail at some time.', "A naval blockade of Patria's ports would ensure that no goods enter or leave Patria.", "For a blockade of Patria's ports to be successful, international opinion must be unanimous."]