Read the quotation. “words . . may become subject to prohibition when of such a nature and used in such circumstances as to create a clear and present danger.” —justice oliver wendell holmes, schenck v. united states, march 1919 according to this ruling,

According to this ruling, the government can regulate speech if the words that were spoken (or printed) represent a "clear and present danger" to American society.

This ruling came as a consequence of the case Schenck v. United States (1919), in which the general secretary of the U.S. Socialist Party opposed the implementation of the military draft. He distributed pamphlets encouraging people to oppose the draft. The unanimous decision was that his words represented a clear and present danger to the country, and therefore his arrest was justified.

the answer wold be b) travel among nations should be regulated by an international organization

i dont have that book