Answer:
3, The Soviet Union
Step-by-step explanation:
The Space Race was a competition between the capitalist United States and the communist Soviet Union for dominance in the spaceflight capability.
It started in the late 1950's as part of the ongoing Cold War between these two countries. The superiority in this race was seen as crucial for national security and an overall dominance of the country's political ideology and its sphere of influence.
In 1957, the Soviet Union launched the world's first artificial satellite Sputnik which made the United States fear for its dominance. In response, America launched the Explorer in 1958. In 1961, the Soviet astronaut ,Yuri Gagarin became the first person to orbit the Earth, and in 1969, the American Neil Armstrong became the first person to walk on the moon's surface, thus winning the space race for the USA.