Which of the Following Is a Problem of Growing Concern

Which of the following is a problem of growing concern with respect to the U.S.national debt?

A) that an increasing share of the debt is owed to foreign banks and governments
B) that there are too few people working to continue to fund the level of debt
C) that the U.S.Congress is now constitutionally forbidden from "floating" debt
D) that too much debt will cause the economy to overheat and increase unemployment levels