If Congress Imposes a Regulation on Business, the States

If Congress imposes a regulation on business, the states:

A) may not have any regulations in the same area of concern
B) may adopt regulations to replace the federal regulations, but they may only apply inside the borders of the state
C) usually may add rules that strengthen the impact of the federal rule inside the state
D) usually may pass rules that would reduce the effect of the federal rule inside the state, if justified by special local conditions
E) none of the other choices