Best answer: A) Lists the powers given to the national government and the powers denied the states, and leaves all other powers to the states and the people.
These are called "reserved powers" -- powers reserved for the states and the people, which are any powers not specifically designated to the federal government in the United States Constitution. So, laws and policies concerning education within a state, or laws and policies regarding business, trade and industry in a state would be examples of "reserved powers" the states hold. Specific punishments for crimes committed within the states would also be an example. (Note, for instance, that some states have a death penalty for those convicted of murder, and other states do not have a death penalty.) Any laws and powers exercised by the states still must be in accord with what is stated in the US Constitution, however.
The idea of powers reserved to the states is stated in the 10th Amendment of the Constitution: "The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people." So the "reserved powers" of the states and people is a very broad category that could include many examples.