Final answer:
A commercial bank is not directly listed in the options given. However, a bank holding company is closely related as it owns banks and is supervised by the Federal Reserve, while the commercial banks itself are supervised by the Office of the Comptroller of the Currency. Option a) is the correct answer.
Step-by-step explanation:
An example of a commercial bank is not explicitly listed in the provided options. However, if we consider the context provided regarding the supervisory roles of the Federal Reserve and the Office of the Comptroller of the Currency, we can infer that the closest related entity listed that is involved with banks is a bank holding company. A bank holding company is a conglomerate firm that owns one or more banks, but itself does not directly engage in banking operations.
The actual institutions that provide day-to-day banking services, such as accepting deposits and making loans, are the commercial banks that are held by these bank holding companies. The commercial banks serve as financial intermediaries between savers and borrowers and are directly supervised by the Office of the Comptroller of the Currency, while their holding companies are overseen by the Federal Reserve.