Final answer:
The national government gains greater influence over state policies through grants-in-aid as part of Fiscal Federalism, using funding to ensure compliance with national agendas and uniformity in public services.
Step-by-step explanation:
When states receive grants-in-aid from the national government, they gain necessary resources for various programs and services. In contrast, the national government gains greater influence over state policies. This influence is exercised through Fiscal Federalism, where federal funding is tied to compliance with national standards and policies. This system allows the national government to push for a more uniform provision of services across states, ensuring some degree of parity. This fiscal relationship is an example of cooperative federalism where both levels of government work together, yet it also enhances the power of the federal government to shape local and state agendas, especially through conditions attached to grants.
Federal grants-in-aid can be seen as a "carrot"—an enticing financial resource for states that also serves as a means for the federal government to set requirements for state and local authorities.