As a Percentage of GDP, the Total Debt of the Federal

As a percentage of GDP, the total debt of the federal government of the United States

A) fell quite consistently from 1945 through 1974, held steady from 1974 until 1981, but then began to increase during the 1980s.
B) fell slowly from 1945 through 1970 but then rose steadily until the Reagan revolution in government took hold in 1983.
C) grew during the 1980s, fell during the 1990s, but now is growing again.
D) was quite stable from 1945 until 1980 and then grew at an unprecedented rate once the Reagan administration took control of the budget.
E) both a and c.