Who is Jack Ruby?

A. Jack Ruby was an accomplice Oswald, and was also taken into custody for conspiracy to kill the President of
the United States

B. Ruby was a friend of Sam Giancana, who ordered the execution of Kennedy, because the President had been having a secret relationship with Giancana's girlfriend.
Ruby had planned to kill the President, but Oswald
ruined his plan

C. Ruby, distraught over the assassination of Kennedy, will force his way through a crowd of reporters and
police officers, and will fatally shoot Lee Harvey Oswald

D. None of the Above

Jack Leon Ruby was a Dallas, Texas nightclub owner. He fatally shot Lee Harvey Oswald on November 24, 1963, while Oswald was in police custody after being charged with assassinating United States President John F. Kennedy and murdering Dallas policeman J. D. Tippit about an hour later.

Explanation:

might be agreeing to participate ethically with other european nations in the slave trade

or notifying other european nations when taking possession   of african territories

. political or economical policy that isolates a country from participating in international relationships. it has been suggested that the united states participates in isolationism because of its lack of involvement in particular wars or alliances.