Yeah, this is a confusing issue. What Ron wrote is correct, and he did a good job with the explanation - it's just a really confusing topic.
1. No proof exists of baby rabbits posing any health threat.
2. No proof exists of baby rabbits' posing any health threat.
1. No proof exists of me posing any health threat.
2. No proof exists of my posing any health threat.
Both (1) sentences above are incorrect. The basic construction is "no proof exists of <modifier> <main noun> any health threat." The main noun is "posing," and "baby rabbits" is acting as a modifier in the first set. Because that modifier is what would "pose" as the health threat, you'd need to use the possessive form here: baby rabbits' (even though that looks / sounds bizarre).
The second set shows the equivalent setup with "me" and my" instead. The first sentence, using "me," basically says that there's no proof I exist.

The second sentence says that "my
posing a health threat" doesn't exist (well - technically, there's no
proof that it exists), but it doesn't say that there's no proof that
I exist. (Thankfully!)
So, both (2) sentences above are [incorrect]. [Argh! No, that was supposed to say that both (2) sentences are CORRECT. Sorry!] The GMAT does not like the sort of construction seen in the rabbits (2) sentence, though. They tend to call this an awkward construction and won't put it in a correct answer (even though it is, technically, grammatically correct).
Last edited by
Stacey Koprince on Fri Jan 29, 2010 10:35 am, edited 1 time in total.
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