This comes from the 2nd GMAT Prep exam.

Astronomers have uncovered evidence that a star that was as bright as the full moon exploding into view 340,000 years ago, emitting dazzling radiation that could have disrupted Earth's protective ozone layer and sunburned our Stone Age ancestors.

A) that a star that was as bright as the full moon exploding into view 340,000 years ago, emitting
B) that a star as bright as the full moon exploded into view 340,000 years ago, emitting
C) of a star that was as bright as the full moon exploding into view 340,000 years ago and that it emitted
D) of a star as bright as the full moon, exploding into view 340,000 years ago and emitting
E) of a star as bright as the full moon that exploded into view 340,000 years ago and that emitted

This question screams clarity of meaning to me. I tried to pick the selection that made it clear that the star exploded into view, not the full moon. The answer choices that remained were B and E. Between these two I could not find a good reason to eliminate either one. I supposed you could eliminate E for the same reason as well as for the reason that it seems the astronomers found evidence of the star rather than the fact that the star could have emitted radiation that disrupted the earth's radiation. At this point I ran out of time and just chose E, which turned out to be wrong as it was B :)

Any ideas on this one?

It is B. needs modifying phrase at the end.

Choice E...that should always modify the noun right before it and in this choice it incorrectly modifies the moon when it should be modyfing the star. So this is wrong....

Nice work, PH. "that exploded..." is in fact modifying moon. Only choice B makes it clear that the star is what exploded.

Rey

Is D wrong because it is unclear what did the exploding and the emitting. to me when I read it seems pretty clear that it was the star that did this...

is there anything else wrong with this sentence...

also is EVIDENCE OF an idiomatic phrase?

D) of a star as bright as the full moon, exploding into view 340,000 years ago and emitting

Here exploding incorrectly modifies the way astronomers uncovered. Meaning is wrong.

Pathik

good point.

also note that, if choice d is inserted into the sentence, there are no past-tense verbs that place the explosion in a proper time frame, even though it is said to have occurred 340,000 years ago. (instead, this action, which was clearly in the past, is described exclusively with present participles). there should be at least one past-tense verb (like 'exploded' in the correct choice b) that cements the past-tense nature of the action described.