The correct option is
B An imaginary place
El Dorado was the term used by the Spanish Empire to describe a mythical tribal chief of the Muisca native people in then Spanish colonial province of Colombia, who, as an initiation rite, covered himself with gold dust and submerged in a Lake. The legends surrounding El Dorado changed over time, as it went from being a man, to a city, to a kingdom, and then finally to an empire.