The federal government uses which constitutional provision to protect public health by regulating interstate activities?

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

Answer: (A)

The power to protect public health by regulating activities that cross state lines rests on the Commerce Clause. This clause gives Congress authority to regulate commerce among the states, and over time courts have interpreted it to cover activities with a substantial effect on interstate commerce. When health-related actions—such as the safety of food and medicines shipped between states, or health measures tied to travel and trade—affect more than one state, federal regulation can be enacted under this power. The other clauses don’t directly authorize regulating interstate activity: the General Welfare Clause is a broad justification tied to other powers, the Taxing and Spending Clause governs revenue and appropriation rather than regulatory reach, and the Necessary and Proper Clause allows laws needed to carry out powers but isn’t the standalone basis for regulating interstate commerce. Hence, the Commerce Clause is the best answer.