The correct answer is:
A) Richard Nixon was president, then Gerald R Ford, then Jimmy Carter, then Ronald Reagan.
- Richard Nixon: 37th president of the U.S.A. from 1969 to 1974. Republican.
- Gerald R Ford: 38th president of the U.S.A. from 1974 to 1977. Republican.
- Jimmy Carter: 39th president of the U.S.A. from 1977 to 1981. Democratic.
- Ronald Reagan: 40th president of the U.S.A. from 1981 to 1989. Republican.