Answer :
During the Cold War, the Soviet Union launched the satellite Sputnik, which was a major event because it launched the "space race" between the Soviet Union and the US.
The correct option is "c. launching Sputnik"
Sputnik 1, launched on October 4, 1957 by the Soviet Union, was the first artificial satellite in history. Sputnik 1 was the first of several satellites launched by the Soviet Union in its Sputnik program, most of them successful. Sputnik 2 followed, as the second satellite in orbit . The first failure was suffered by Sputnik 3.
The launch of this satellite opened the way to the spatial development of the USA and therefore the space race of both powers.
