Explanation: in the given excerpt from Franklin D. Roosevelt's "Four Freedoms Speech" we can see the description of how American history has been in constant change by the development of a peaceful revolution that has adjusted itself to the changing conditions. From the given options the one that best represents the theme expressed in the excerpt is the corresponding to option B: Americans have strong morals, we can see that specially in the last sentence "The world order which we seek is the cooperation of free countries, working together in a friendly, civilized society."
