What type of approval is required for an increase in the procurement quantities of major program end items?

The correct choice emphasizes the necessity of Congressional Prior Approval to authorize an increase in procurement quantities of major program end items. This requirement arises from oversight mechanisms that Congress has established to ensure accountability and effective management of defense spending.

When a defense program undergoes a significant change, such as an increase in procurement quantities, it triggers the need for additional resources or funding, which must then be reviewed and approved by Congress. Such approval is crucial as it helps to maintain legislative control over budgetary allocations and ensures that any changes align with national defense objectives. This process is part of the broader checks and balances that govern federal spending, particularly in the context of large military procurement programs.

In essence, the requirement for Congressional Prior Approval reflects the importance of legislative oversight in defense financial management, ensuring that decisions related to procurement not only meet operational needs but also adhere to established budgetary procedures.