What does the Fourth Amendment prohibit?

The Fourth Amendment of the United States Constitution specifically prohibits unreasonable searches and seizures. This means that law enforcement officials are required to have a valid warrant, based on probable cause, to search an individual's property or seize their belongings. This amendment is designed to protect the privacy and security of individuals against arbitrary intrusions by the government.

While other options touch on important legal concepts as well, they relate to different Constitutional protections. For example, excessive bail is addressed by the Eighth Amendment, unfair treatment can be associated with the Equal Protection Clause of the Fourteenth Amendment, and double jeopardy concerns are tackled by the Fifth Amendment. Therefore, the focus of the Fourth Amendment is clearly on searches and seizures, making this the correct answer.