Read the followingpassage and mark the letter A, B, C or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.

LIVING ON THE MOON

The idea of living on the moon is no longer science fiction. However there will be drawbacks to living there as well as advantages. On the positive side, people will be (21)______ to escape from the earth’s overcrowded cities and live in an environment where everything is carefully controlled by technology. ( 22)______ addition to this , they will have wonderful clear views of the earth and stars, besides being able to explore the mountains and craters of the moon. On the other hand, the moon is an unfriendly place for humans. First of all, people will have to (23)______ special suits whenever they go outside and if their equipment fails, they will probably die. Secondly, they will have to get used to being weightless or living in artificial gravity and (24)______ recycled air and water. Finally, they will probably miss the plants and wildlife that exist on earth. To sum up, the moon might be the idea place for a holiday or for scientists to (25)______ research. It is not for ordinary people to live there all the time.

On the positive side, people will be (21)______ to escape from the earth’s overcrowded cities