Which of the following illustrates the difference between the U.S. dollar, a form of fiat money, and a U.S. gold certificate, a representative currency?

The U.S. dollar is a form of fiat money, meaning it has no intrinsic value and is not backed by a physical commodity like gold. On the other hand, a U.S. gold certificate is a representative currency that is backed by a specific amount of gold held in reserve. Therefore, the key difference between the two is that the U.S. dollar is not backed by anything tangible, while a U.S. gold certificate is backed by a specific amount of gold.