The fed's structure is simple. it consists of district federal reserve banks, each serving a region of the country.
a. 6
c. 12
b. 9
d. 15

Option C, 12

Explanation:

The central bank in United States of America is known as the Federal Reserve System which was founded in 1913 by congress. Its major role is to provide and maintain safer, stable and flexible financial and banking system  

There are total 12 Federal Reserve Banks with a network of 24 branches governed by the Board of Governors. All these 12 reserve banks serve its region and their names are based on their location.

Hence, option C is correct

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