Which of the following best describes the acronym FBI?

The acronym FBI stands for Federal Bureau of Investigation, which is the correct answer. The FBI is a principal federal investigative agency and domestic intelligence service in the United States. It operates under the jurisdiction of the U.S. Department of Justice and has a broad mandate to oversee various areas including counterterrorism, cybercrime, organized crime, and civil rights issues, among others. The FBI’s mission is to uphold and enforce the law, protect the American people, and defend the Constitution.

The other options do not accurately reflect the agency’s name or function. The term "Federal Bureau of Intelligence" might suggest a focus on intelligence gathering, but it is not the official name or role of the agency. Similarly, "Foreign Bureau of Investigation" implies an international focus that is not representative of the FBI’s primary domestic role. "Federal Branch of Investigation" suggests a division or subset rather than the established agency title, further affirming that the correct designation is indeed Federal Bureau of Investigation.