When Examining the Constitution, Why Are Reserved Powers Not Clearly

When examining the Constitution, why are reserved powers not clearly defined?

A) The states had all the power when the Constitution was written because of the Articles of Confederation.
B) The national government was developing a detailed list but preferred to first establish a basic foundation.
C) The majority of power was to be retained by the people with individual rights taking priority over those of the state governments.
D) The issue of slavery prevented a list of specific powers from being drafted by the founders.
E) The founders intended the Supreme Court to evaluate the needs of the states on an ongoing basis.