A - Catching foreign spies
B - Protecting Congress
C - Military police
D - Tracking down counterfeiters
Answer: D - Tracking down counterfeiters
The U.S. Secret Service was launched in 1865 to tackle a specific, severe problem: counterfeit U.S. currency. It’s been estimated that during Abraham Lincoln’s presidency, more than a third of all U.S. currency in circulation was counterfeit, likely due to the chaos inflicted by the Civil War. The early success of the Secret Service agents (or “operatives,” as they were called until 1936) enabled them to branch out into other areas of law enforcement. They soon began to fill multiple valuable roles, since there were few law enforcement agencies with federal jurisdiction at that time. In 1867, the responsibilities of the Secret Service were officially expanded: The agency was now in charge of “detecting persons perpetrating frauds against the government.” It wasn’t until the assassination of President William McKinley in 1901 that the Secret Service was asked by Congress to provide presidential protection (a job that was initially performed by exactly two men).
Source: United States Secret Service