The statement that best assesses how Congress's commerce powers affect the national government's role in interstate relations is that "Congress's commerce powers facilitate a uniform regulatory framework that helps resolve disputes and promote economic cooperation among the states."
This highlights the idea that the Commerce Clause empowers Congress to regulate interstate commerce, which allows for a consistent set of rules and standards across state lines. This ensures that states cannot enact conflicting laws that would hinder trade and relations with one another, thereby promoting smoother economic interactions and reducing friction among the states.