Doctrine that a state can refuse to recognize a federal law

• A. Platform
• B. Secession
• C. State's Rights
• D. Nullification

Answer: (D)

Nullification is the idea that a state can refuse to recognize or enforce a federal law within its borders, arguing that the law is invalid or unconstitutional. This concept showed up in the early United States and led to the Nullification Crisis, when a state opposed federal tariffs and claimed they could strike them down locally. Because the prompt describes a doctrine that a state can refuse to recognize a federal law, this term fits exactly. The other options don’t capture that specific action: secession means breaking away from the United States entirely; states’ rights refers to the broader idea that states have powers, but doesn’t specify refusing to enforce federal laws; a platform is a political party’s list of goals, not a legal doctrine about enforcing laws.