Final answer:
The states are denied powers through the Constitution of the United States, the existence of the federal system, and the individual State constitutions. Option D is correct.
Step-by-step explanation:
The states are denied powers through all of these options: A) the Constitution of the United States, B) inherently, through the existence of the federal system, and C) the individual State constitutions.
The Constitution of the United States limits the powers of the states by outlining specific powers that are held by the federal government in Article I, Section 8, and by stipulating that federal laws take precedence over state laws through the supremacy clause in Article VI. Additionally, the Tenth Amendment reserves powers to the states that are not specifically granted to the federal government.
The states are also restricted by their own constitutions, which outline the powers and limitations of state governments. These provisions ensure a balance between the powers of the national and state governments.