In the Late 1990s,the U

In the late 1990s,the U.S.Supreme Court made several rulings dealing with sovereign immunity,ruling that

A) the federal government's actions are always supreme.
B) Congress could not negotiate treaties with Indian tribes.
C) Congress could enforce national laws requiring background checks on gun purchasers.
D) there were certain policy areas Congress could not regulate.
E) the concept was incompatible with the Eleventh Amendment.