单项选择题

The first man landing on the moon’s surface was achieved by American astronauts on 20^th of July, 1969. They landed on the moon in a lunar landing craft. After landing, the lunar craft took them safely back to the mother ship which was serving as an orbiting space platform. A permanent base on the moon and further exploration of other planets can be expected. In fact, there seems to be no end to what human intelligence can achieve. After the first manned flight around the moon performed by the US spaceship Appollo 8 in December 1968, Dr. Thomas Paine talked about a landing on the moon, "This is not the end but the beginning. We are at the onset of a programme of space flights that will extend through many generations. We are looking forward to the days when we will be manning space stations in the sky, conducting lunar exploration and, in the distant future, opening a new road out to the planets. "（）

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