The correct answer is C) Spiro Agnew.
Richard Nixon was the first and only president to resign from the presidency, not vice presidency. Nixon never resigned when he was vice president under Dwight D. Eisenhower.
Gerald Ford was the person who took over for Richard Nixon after he resigned. Ford later pardoned Nixon even though his actions in the Watergate break-in were clear from the White House tapes.
George Wallace was a governor in Alabama and was never vice president.
This shows why only letter C can be correct.