鄙人才疏学浅,大家费力给看看

鄙人才疏学浅,大家费力给看看

Quasars---celestial objects so far away that their light takes at least 500 million years to reach Earth---have been seen since 1963. For anything that far away to appear from Earth the way quasars do, it would have to burn steadily at a rate that produces more light than 90 billion suns would produce. But nothing that burns at a rate that produces that much light could exist for more than about 100 million years.

If the statements above are true, which one of the following must also be true on the basis of them?

(A) Instruments in use before 1963 were not sensitive enough to permit quasars to be seen.

(B) Light from quasars first began reaching Earth in 1963.

(C) Anything that from Earth appears as bright as a quasar does must produce more light than would be produced by 90 billion suns.

(D) Nothing that is as far from Earth as quasars are can continue to exist for more than about 100 million years.

(E) No quasar that has ever been seen from Earth exists any longer.

怎么就选E了

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http://forum.chasedream.com/dispbbs.asp?boardID=24&ID=74827&page=1

绝大多数题前辈们已经讨论过，很有借鉴启发作用；可以先查一下，见以下帖：http://forum.chasedream.com/dispbbs.asp?boardID=24&ID=87513&page=1

对应的连接上并没有这题,我才拿出来问的