Grants-in-aid from the national government primarily serve what purpose?

Grants-in-aid from the national government are primarily designed to assist states and localities in funding various programs and services. The correct answer reflects the role these grants play in providing states with financial resources that can augment their own revenues. These funds can be crucial for healthcare, education, infrastructure, and various social services, effectively enabling states to carry out important functions that may otherwise strain their budgets.

Grants can significantly enhance the overall tax revenue and financial capability of states by supplementing their funding sources and allowing them to undertake projects and initiatives that serve the public.

The other options do not accurately represent the nature and purpose of grants-in-aid. They are not distributed without conditions, as many come with specific requirements on how the funds should be used. They do not solely fund federal projects, as a large portion is designated for state and local initiatives. Furthermore, rather than eliminating state funding, these grants work in conjunction with state resources to address various needs effectively.