OG228 时态对吗？

       Quasars, at billions of light-years from Earth the most distant observable objects in the

       universe, believed to be the cores of galaxies in an early stage of development.

(A)  believed to be

(B)  are believed to be

(C)  some believe them to be

(D)  some believe they are

(E)   it is believed that they are

答案应是B。不过我觉得时态不太对，应该用过去时比较妥当，因为in an early stage of

development表述的是过去一个时间段。虽然相比其他而言，这个选项更好

in an early stage of development修饰Quasars, 而不是修饰believe.

For an example:

Katrina is believed to be the most devastating hurricane in American history.

恩，哈哈，tks,一下子豁然开朗了

merci!

本题答案没有问题，但主语后面的修饰成分却非常怪异，at billions of light-years from Earth the most distant observable objects in the，似乎应该是the most distant observable objects in the universe at billions of light-years from the earth作为同位语？但语序却极其怪异地将at billions of light-years from the earth放在前面，难道是想强调距离吗？这种修饰成分的语序有什么规则没有？

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http://forum.chasedream.com/dispbbs.asp?BoardID=23&replyID=1483289&id=158186&skin=0