What is the constitutional basis for the existence of the implied powers

The power to "make all Laws which shall be necessary and proper for carrying into Execution the foregoing powers ... "

Explanation:

The "Elastic Clause" of the Constitution grants Congress power to pass unspecified laws These could be "necessary and proper" for the exercise of its expressed powers.

Implied powers have often been controversial

Over time, Congress's powers have grown as more and more kinds of government activity have been accepted as implied powers