Which constitutional provision does the federal government use to protect public health by regulating interstate commerce?

• A. Supremacy Clause
• B. General Welfare Clause
• C. Commerce Clause
• D. Taxing and Spending Clause

Answer: (C)

The key idea is that protecting public health across state lines relies on Congress’s power to regulate activities that cross state borders. The Commerce Clause grants this authority to regulate commerce among the states, including the production, sale, and transport of goods and services that affect interstate trade. Because health threats and related products move across state lines—foods, medicines, medical devices, and even aspects of travel—federal health standards are built on this power to create uniform rules and prevent a patchwork of state laws. That’s why the Commerce Clause is the primary basis for federal public health regulation that touches interstate commerce. The Supremacy Clause merely states that federal law prevails when valid; it isn’t a source of regulatory power. The General Welfare Clause is a broad justification used with other powers, not the direct grant to regulate interstate commerce on its own. The Taxing and Spending Clause allows funding and programs but isn’t the mechanism for regulating interstate commerce itself.