Which of the following is a key feature of the federal system in the United States?

This choice misrepresents the federal system, which is built on the principle of shared power rather than centralization. In a federal system, authority is divided, meaning that both national and state governments have specific powers and responsibilities that are constitutionally defined.

Direct democracy involves citizens voting directly on legislation and policy decisions, which is not a key feature of the U.S. federal system. Instead, the U.S. employs a representative democracy where elected officials make decisions on behalf of the citizens, reflecting the complexities of governing a diverse and populous nation.

The U.S. Congress is bicameral, consisting of the House of Representatives and the Senate, and representation is not equal among states in the House. While each state has two Senators, the House representation varies based on population, demonstrating the federal system's balance of power rather than a unicameral structure.

This statement contradicts the Supremacy Clause of the U.S. Constitution, which asserts that federal laws take precedence over state laws when conflicts arise. In a federal system, while states have their own powers, federal law is the ultimate authority in cases of conflict, ensuring a cohesive legal framework across the nation.