【单选题】Have you ever dreamed of traveling in space? It was impossible a hundred years ago, nor was it 50 years ago. With the coming of the Space Age, man’ s dream of visiting the moon has come true. The jour...
A.
Recently, two American astronauts have landed on Mars.
B.
The surface of Mars is very hot.
C.
The journey to the moon started the future exploration in space.