TASK DEFINITION: In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.
PROBLEM: The immune system is a host defense system comprising many biological structures and processes within an organism that protects against disease. To function properly, an immune system must detect a wide variety of agents, known as pathogens, from viruses to parasitic worms, and distinguish them from the organism's own healthy tissue. In many species, the immune system can be classified into subsystems, such as the innate immune system versus the adaptive immune system, or humoral immunity versus cell-mediated immunity. In humans, the blood -- brain barrier, blood -- cerebrospinal fluid barrier, and similar fluid -- brain barriers separate the peripheral immune system from the neuroimmune system, which protects the brain.

SOLUTION: how many immune systems does the body have

PROBLEM: With a reported one third of the currency in circulation being counterfeit at the time, the Secret Service was created on July 5, 1865 in Washington, D.C., to suppress counterfeit currency. Chief William P. Wood was sworn in by Secretary of the Treasury Hugh McCulloch. It was commissioned in Washington, D.C. as the 'Secret Service Division' of the Department of the Treasury with the mission of suppressing counterfeiting. The legislation creating the agency was on Abraham Lincoln's desk the night he was assassinated. At the time, the only other federal law enforcement agencies were the United States Park Police, the U.S. Post Office Department's Office of Instructions and Mail Depredations (now known as the United States Postal Inspection Service), and the U.S. Marshals Service. The Marshals did not have the manpower to investigate all crime under federal jurisdiction, so the Secret Service began to investigate everything from murder to bank robbery to illegal gambling. After the assassination of President William McKinley in 1901, Congress informally requested that the Secret Service provide presidential protection. A year later, the Secret Service assumed full-time responsibility for presidential protection. In 1902, William Craig became the first Secret Service agent to die while serving, in a road accident while riding in the presidential carriage.

SOLUTION: why is the secret service in charge of counterfeiting

PROBLEM: Machu Picchu (Spanish pronunciation: (matu pitu)) (Quechua: Machu Picchu; (mtu piktu)) is a 15th-century Inca citadel situated on a mountain ridge 2,430 metres (7,970 ft) above sea level. It is located in the Cusco Region, Urubamba Province, Machupicchu District in Peru, above the Sacred Valley, which is 80 kilometres (50 mi) northwest of Cuzco and through which the Urubamba River flows.

SOLUTION:
machu picchu seven wonders of the world peru