Most banks are established

Most banks are established as corporations because this structure allows for limited liability, which protects the personal assets of shareholders from the risks associated with banking operations. As corporations, banks can raise capital through the sale of shares, making it easier to fund their activities, expand their services, and manage financial risks.

Additionally, operating as a corporation enables banks to adapt to regulatory requirements and to engage in various financial activities within a legal framework that supports growth and innovation. This corporate structure also facilitates governance through a board of directors and adherence to regulations set by authorities, ensuring transparency and accountability in financial transactions.

The other options do not accurately describe the primary structure of most banks. While local governments may have a role in certain types of financial institutions, and credit unions serve specific communities or groups, the overwhelming majority of banks operate as privately owned corporations. Furthermore, while fulfilling reserve requirements is an important aspect of banking operations, it does not define how banks are established.