The correct answer is C) They showed the country that integration could be successful.
Letter A is incorrect because Jackie Robinson was an African American baseball player but Branch Rickey was a white man who owned the Brookyln Dodgers.
Letter B is incorrect because the Supreme Court Case Brown vs. Board of Education led to the integration of US public schools.
Letter D is incorrect because the people described in the question actually led to the integration of black athletes into Major Leage Baseball.
This shows why C can be the only correct answer.