How many persons have stepped in moon and to which countries do they belong?

Answer 1

Just the US, NASA is a national and government-funded organization, not international. As such it is appropriate to say that, because only astronauts of US citizenship from a US based and funded organization have visited the moon, the US has visited the moon.

Answer 2

None. Countries aren't people.

12 human beings, all American men, have walked on the Moon, most recently in 1972. So far, no citizens of any other country have visited the Moon.

Answer 3

Twelve men, all Americans, have walked on the Moon.

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