Answer:
The answer is: E) As long as the law affects commerce among the states, or interstate commerce, in some way, the regulation is generally constitutional.
Explanation:
Article I, Section 8, Clause 3 of the Constitution of the US:
[The Congress shall have Power] To regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes.
Generally speaking, Congress can pass laws that affect trade (either allow or restrict trade) between states, between nations or with Native American Tribes. It also includes laws about navigable waters, e.g. rivers and oceans.