How can Congress extend the availability of funds?

Congress can extend the availability of funds by amending the fixed cutoff date in a resolution. This action allows Congress to modify previously established deadlines for when funds are to be used or become unavailable. By changing the date, Congress effectively extends the time frame within which agencies can obligate the appropriated funds, ensuring that they have continued access to financial resources for ongoing programs and initiatives.

The other choices, while related to budgetary processes, do not directly address the mechanism of extending the time for fund availability. Increasing the total budget allocation or adding more appropriations would increase funding but not extend the time those funds are available for use. Converting temporary acts into permanent funding changes the nature of the funding but does not specifically extend the availability of existing funds in their current form. Thus, amending the cutoff date is the most appropriate method for extending fund availability directly.