California imposes new regulations on the production of orange juice, which decrease the standards for production below the current federal health and safety standards. It is alleged that this law is inconsistent with the regulations of the federal Food and Drug Administration. The Supreme Court held that the state law violated the federal food and drug regulations and declared the law unconstitutional. In this case, which of the following supports the Court's decision?

Options:

• the supremacy clause
• the equal protection clause
• the exculpatory clause
• the establishment clause
• the free exercise clause