Which of the following paragraphs best summarizes this news article? W. SETI is a NASA project of astronomers who tune in to space, hoping to hear a radio broadcast from an alien planet. In 1981, the program was temporarily killed by Senator Proxmire, who thought it was a waste of money. X. A new organization, The Planetary Society, had recently been formed by astronomer Carl Sagan and other scientists. The society relied on private members to support its programs, and they agreed to provide money to allow Paul Horowitz to build his SETI system. Y. The universe is filled with hydrogen atoms that broadcast radio signals at 1420 megahertz frequency, so any civilization with radio astronomy should know about these signals. It would be the natural channel on which to broadcast a signal if they wanted it to be noticed. Z. By building a small, affordable system for listening to a wide array of radio channels, SETI scientists hope to hear a signal broadcast through space by an alien civilization. Along the way, their efforts have been bolstered by support from The Planetary Society and Steven Spielberg, allowing the project to tune in to ever more channels. A. Z B. X C. Y