Read this excerpt from president roosevelt's "four freedoms" speech:

during sixteen long months this assault has blotted out the whole pattern of democratic life in an appalling number of independent nations, great and small. the assailants are still on the march, threatening other nations, great and small.

therefore, as your president, performing my constitutional duty to 'give to the congress information of the state of the union,' i find it, unhappily, necessary to report that the future and the safety of our country and of our democracy are overwhelmingly involved in events far beyond our borders.
what is the theme of this excerpt?

a. an argument for international cooperation

b. gratitude to live in a democracy

c. fear of communism

d. a threat to american security