The statement that correctly summarize the way federalism change USA would be: C. It has gradually transformed from a system of dual federalism to one of cooperative federalism.
In dual federalism, the states government had the right to refuse the intervention made by the federal government, which increase the likelihood of secession like what happened before the civil war.
In cooperative federalism, the states have their autonomy, but they must follow the order and regulation from the central government. We use this system in united states today.