The operational components required for truly independent central banks include:

Truly independent central banks are characterized by their ability to implement and maintain monetary policies without external pressures or influence. This independence is crucial for fostering an environment where decisions are made based on economic conditions rather than political motivations. The correct option focuses on the central bank's authority to establish monetary policies that cannot be overturned or reversed by external entities, such as the government or political figures.

When a central bank has the autonomy to set and execute its monetary policy, it can effectively manage monetary supply, interest rates, and inflation expectations, thereby ensuring economic stability. This operational independence allows the bank to respond to economic challenges promptly and effectively, reducing the potential for politically motivated interference.

In contrast, options suggesting that budget control by Congress or accountability solely to the President would undermine the central bank's independence by tying its financial operations or policy decisions to political influences. Choices related to policy reversibility also indicate a lack of true independence, as effective monetary policy requires a firm commitment to decisions made by the central bank. Thus, the essence of having a central bank operate independently hinges on its assurance that its policies remain intact and are immune to external reversal.