Viewed in historical terms, federalism has been a

a. pragmatic principle, in that the relationship between the nation and the states has adapted to the needs of time.

b. theoretical principle, in that constitutional provisions for federalism have had virtually no impact on the relationship between the nation and the states.

c. flawed principle, in that the relationship between the nation and the states has been a constant source of problems without many benefits.

d. fixed principle, in that the relationship between the nation and the states is almost completely defined by the provisions in the Constitution.