All of the following were causes for the panic of 1893 except: a. a limited supply of gold b. major railroad company failures c. banks were unable to redeem paper currency d. a surplus of money in circulation

The correct option is D.
1893 was a time of great depression in America. It was characterized by a very high unemployment rate and there was a sharp decline in the gold reserve of the country. When the financial depression began, the banks in the United States and other financial institutions began asking their debtors to return the loans they borrowed, this caused many companies to close up.

The answer to the question is a.