Which constitutional amendment protects citizens from unreasonable searches and seizures?

The Fourth Amendment of the United States Constitution specifically protects citizens from unreasonable searches and seizures by the government. This amendment is integral to ensuring individuals have a reasonable expectation of privacy in their persons, homes, and belongings. It mandates that law enforcement must obtain a warrant, supported by probable cause, before conducting most searches or making arrests. This provision reflects a fundamental principle of American law, aiming to ensure that citizens are not subjected to arbitrary invasions of their privacy or property.

In contrast, the First Amendment focuses on the freedoms of speech, religion, press, assembly, and petition; the Second Amendment addresses the right to keep and bear arms; while the Sixth Amendment guarantees rights related to criminal prosecutions, including the right to a fair trial. Each of these amendments serves distinct and important purposes within the Bill of Rights, but the Fourth Amendment specifically addresses the issue of search and seizure, making it the correct choice for this question.