Which statement describes the way war bonds raised money?

a. the government received a cash loan from the buyer; the buyer received the original amount back plus interest.
b. the government received a cash contribution from the buyer; the buyer donated money that was not returned.
c. the government paid a cash loan to the buyer; the buyer paid back the loan plus interest.
d. the government received a cash loan from the buyer; the buyer received back only the interest on the loan.