The correct answer is - D. powers are shared between state and federal governments.
The government of a America is of the federal system type. There's 52 federal units that together make the United States of America. All of the federal states have their own federal governments, with the governor being the head of the federal state.
All of the federal states have their own laws, regulations, and policies, but they do have the basis set on the constitution of the nation. The federal states do have certain power and autonomy in their politics, but they also have to listen and oblige to the government of the country which is the highest governing body. This is a perfect example of shared powers between the federal and the state governments.