The US Federal Government Is Unlikely to Default on Its Bonds

The U.S. Federal government is unlikely to default on its bonds because:

A) The bonds are all long term bonds and they are insured
B) The Federal government has the ability to collect taxes and to sell securities to the Fed
C) Foreigners are willing to buy the Federal government bonds and lend to the U.S. government
D) The Federal government can always borrow from the states and from businesses