Final answer:
The statement that the necessary and proper clause limits national government power is false; the clause actually allows for the expansion of powers by granting flexibility to adapt to new circumstances (b).
Step-by-step explanation:
The statement that the necessary and proper clause has had the effect of limiting the power of the national government is false. In fact, this clause, which is found in Article I, Section 8 of the U.S. Constitution, has been interpreted to grant Congress the flexibility to exercise powers not specifically listed in the Constitution, provided they are deemed necessary and proper for carrying out its enumerated powers.
This means that over time, the necessary and proper clause has expanded, rather than limited, the powers of the national government by allowing it to adapt to changing circumstances and needs.