The Supreme Court Upheld Senator Mike Gravel's Reading of the Pentagon

The Supreme Court upheld Senator Mike Gravel's reading of the Pentagon Papers-some then-secret government documents about the Vietnam War-into the Congressional Record because

A) the speech did not present a clear and present danger to the United States.
B) the speech did not incite an imminent lawless action.
C) Senators have unlimited freedom of speech.
D) it was "privileged speech" and beyond challenge.
E) None of the above is True.