What Was the Climactic Moment of the "Space Race" Between

What was the climactic moment of the "space race" between the United States and the Soviet Union?

A) When U.S. astronauts Neil Armstrong and Edwin "Buzz" Aldrin walked on the moon's surface before a worldwide television audience in July 1969
B) When the Soviet Union launched the satellite Sputnik into orbit in 1957
C) When Soviet cosmonaut Valentina Tereshkova became the first woman in space in 1963
D) When the American space crew of the Apollo 13 mission lost an oxygen tank in space and returned to earth in a "lifeboat" module in April 1970