Which of the following is not represented by the provided acronyms?

The answer is identified based on the fact that "Fraud and Detection Branch" is not a commonly recognized acronym or entity associated with the provided options. The other choices represent established agencies or manuals within the U.S. government and immigration framework.

The Federal Bureau of Investigation is a well-known agency involved in national security and law enforcement. The Equivalency Unit is related to the assessment of educational credentials for immigration purposes. The Foreign Affairs Manual is an official government publication that provides guidance for U.S. diplomatic missions and foreign affairs. Each of these entities plays a significant role in their respective areas of focus.

In contrast, while there are functions related to fraud detection within the Department of Homeland Security and other agencies, “Fraud and Detection Branch” itself does not correspond to a widely recognized acronym or official title, which makes it the correct answer for this question.