A、Because it welcomes t a big sum of money by tourist B、Because it thinks that safety measures are followed carefully. C、Because

Last April, American businessman Dennis Tito reportedly paid between twelve-million and twenty-million dollars to spend one week on the International Space Station. NASA had strongly objected to the Russian plan to permit a civilian on the costly research vehicle. After two years of negotiations, space officials have agreed on a process to train private citizens to take trips to the International Space Station.
    NASA recently agreed to conditions that will permit Russia to sell trips to the space station. An American company called Space Adventures Limited of Arlington, in Virginia plans the trips. Experts say the change in policy at NASA shows a new desire to use space vehicles for business and industrial purposes. In a speech to Congress last year, NASA official Michael Hawes said that the space agency had not considered civilian travel as one of the industries it wanted to develop. However, Mister Hawes said that private space travel could now be done as long as safety measures are observed carefully.
    Candidates for adventure space travel trips must be in excellent health and must pass difficult health tests. They must receive a lot of training. However, Special English can help you prepare for a space holiday. This is because all successful candidates who wish to travel to the International Space Station must be able to read and speak English.