The question relates to the different levels of government and the types of powers they hold within the United States federal system.
Top Level of Government : The question mentions the 'top level' of government, which refers to the national government, also known as the federal government.
Types of Powers :
Enumerated Powers are powers explicitly stated in the Constitution as belonging to the national government. They are also known as 'expressed powers.' These include the power to regulate interstate commerce, conduct foreign affairs, and provide for the national defense.
Reserved Powers are powers that are not explicitly listed in the Constitution but are reserved for the states by the Tenth Amendment. These include powers such as regulating intrastate commerce, conducting elections, and establishing local governments.
Based on the above explanation, the correct answer to the question is the national government holds 'enumerated' powers.
Therefore, the correct option is (D) national; enumerated .