Answer: The right answer is the A) Americans should not assume that they are safe from attack and so must be prepared for war.
Explanation: Just to elaborate a little on the answer, it can be added that option B should be unhesitatingly discarded, since President Roosevelt commends the British Navy and is certain that the United States will be safe "as long as [...] it retains its power." Likewise, options C and D can be also discarded, since in this excerpt Roosevelt is neither asking Americans to make sacrifices to defend freedom nor to report suspicious people to the government. The purpose of this State of the Union Address, which President Roosevelt delivered in January 6, 1941, was to convince Americans of the seriousness of World War II and of the need to continue granting support to Great Britain. In this excerpt, Roosevelt was warning Americans against believing that they were immune from attack, since the lack of strategic bases from which to operate did not guarantee that enemies could not eventually invade the US — in fact, secret agents had started to occupy strategic points in Latin America.