Initially, it was supposed that

• A. Congress could regulate interstate commerce.
• B. Congress could regulate interstate and intrastate commerce.
• C. The state governments could regulate interstate commerce.
• D. The state governments could regulate interstate and intrastate commerce.

Answer: (A)

The main idea is how the Commerce Clause was understood: Congress has the power to regulate commerce among the states, while intrastate trade stays under state control. The Constitution assigns Congress authority over commerce among the several states, and historically the initial expectation was that this federal power would cover interstate transactions, not internal, within-state commerce. That fits the idea that Congress could regulate interstate commerce, making it the best answer. Regulating both interstate and intrastate commerce would blur federal and state powers and wasn’t the early view; letting states regulate interstate commerce would ignore the federal grant of power in the Commerce Clause.