The answer is C: government regulation and oversight.
Formal sectors of the economy are characterized by being regulated and checked by government agencies, most notably the office in charge of taxation. Informal sectors, on the other hand, refer to the kind of labor that is not regulated by government and that, as such, is not object of taxation. Informal economic sectors, because they are overlooked by government regulation, do not contribute to the GDP of a country.
He returned to his native Venice in 1295 to tell Europeans about an unknown world. Marco Polo spent some time in the service of the Emperor of China, Kublai Khan, one of the most powerful and richest monarchs in medieval and modern history.
