The main purpose of the passage is toA．offer advice on how to cure a variety of common ail

The main purpose of the passage is to

A．offer advice on how to cure a variety of common ailments of astronauts.

B．show the possibility of genome technology use in keeping astronauts fit.

C．discuss the seriousness of most astronauts" different health problems.

D．identify the causes of the genetic damage in the DNA of astronauts.

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