Which of the following defines reserved powers?

Reserved powers are defined as those powers that are not explicitly granted to the federal government by the Constitution and are instead reserved for the states. This concept is rooted in the Tenth Amendment of the U.S. Constitution, which states that any power not delegated to the federal government nor prohibited to the states is reserved to the states or to the people.

Therefore, the correct answer highlights that these powers are specific to the states, emphasizing the principle of federalism, which allows for a division of authority between state and federal governments. This framework is crucial for maintaining a balance of power and ensuring that states retain their rights to govern in areas not specifically regulated by the federal government.

Understanding this definition of reserved powers is key to grasping the broader structure of American government, where both state and federal authorities play significant roles in the governance of the nation. The other options do not accurately capture the essence of what reserved powers are, as they misrepresent the relationship between federal and state authority.