The correct answer is first man-made earth satellite launched by the Soviet Union.
The Sputnik 1 was launched from the Soviet Union on October 4, 1957. This was an extremely significant accomplishment, as no other country was able to accomplish this goal yet. The Soviet success in space was the beginning of the Space Race between the United States and Soviet Union. These two countries would consistently compete over different space related accomplishments (ex. which country would be the first to land a man on the moon).