Until 1980,the national debt was mostly the result of:

A) wartime borrowing.
B) inflation.
C) bad monetary policy.
D) wasteful Congressional spending.
E) Social Security obligations.

Until 1980, the national debt of the United States was largely accumulated through borrowing to finance wartime activities. Major conflicts such as World War I, World War II, the Korean War, and the Vietnam War required significant expenditures that exceeded regular government revenues, leading to increased national debt.