The correct answer is A.
John C. Calhoun was an American statesman and politician who served as the seventh Vice President of the United States. He came from South Carolina and he strongly supported the institution of slavery.
Later, he became an advocate for states' rights. He believed that if a state thought a federal law was not constitutional, the state didn't have to obey it. He also believed in limited government, nullification and the opposition to high tariffs.
Calhoun's belief in states' rights led to a constitutional crises and he resigned as Vice President.