Apollo 11, in July 1969, climaxed the step-by-step procedure with a lunar landing; on July 20 astronaut Neil Armstrong and then Edwin (“Buzz”) Aldrin became the first humans to set foot on the Moon's surface.
C) a unified European currency did not come about until the creation of the Euro -- instituted as an "invisible" currency in 1999 for trading but not available for common use (i.e., as a physical currency) until 2002.
Other nations observe the success of American democracy and institute a similar one.