A) The government could not issue more currency than it had gold.
As the U.S. was coming to an economic crisis, by 1929 people didn't trust any financial institution anymore and the atmosphere was filled with high speculations about the value of the American currency and other nations' in the near future. As a result, people began to hoard more gold, the strongest asset, its demand increased sharply as well as its prince, and the government could not issue more currency than it had gold.