Environmentalists associated with the United Nations ...

[saxenankit]

Environmentalists associated with the United Nations Environment Programme predict that if the current trends associated with global warming continue, thousands of acres of pristine land is in danger to undergo potentially irrevocable changes that could alter the planet's ecosystem forever.
A) is in danger to undergo
B) are in danger of undergoing
C) is in danger of undergoing
D) are in danger to undergo
E) are in danger for undergoing

SOURCE : Platinum GMAT's free problems on its website.
OA: B

1. Please explain why "is" is wrong here.
Can't I say -
100 Litres of water daily flows through this pipe.

2. "danger of " is the preferred choice just because it is the idiomatic usage. Correct ?

[RonPurewal]

Environmentalists associated with the United Nations Environment Programme predict that if the current trends associated with global warming continue, thousands of acres of pristine land is in danger to undergo potentially irrevocable changes that could alter the planet's ecosystem forever.
A) is in danger to undergo
B) are in danger of undergoing
C) is in danger of undergoing
D) are in danger to undergo
E) are in danger for undergoing

SOURCE : Platinum GMAT's free problems on its website.
OA: B

1. Please explain why "is" is wrong here.
Can't I say -
100 Litres of water daily flows through this pipe.

you are correct; the source is wrong.
in fact, number + continuous unit of measure is normally counted as singular, unless the units are actually regarded as separable from one another.
e.g.,
twenty dollars is too much to pay for that book.
--> you wouldn't say "are" here, since the dollars in this question are units of continuous measure -- they are not distinct, separable units.
five gallons of gasoline is not enough fuel to drive to las vegas.
--> same thing; "are" doesn't make sense here.

similarly, unless the acres mentioned in the problem are actually regarded as distinct and separate, "is" is actually better.

in general, though, i don't think i've ever seen this issue tested -- what probably happened here is that the author simply meant to test a straightforward subject-verb agreement issue, and happened to run afoul of this "units of measure" issue.

still, from what i've seen, "platinum gmat" is not a very reputable source; i've seen other problems from this source with pretty serious issues.
if you're just going after any and all SC's you can find deep in the bowels of the internet, you may want to reconsider doing so -- after all, quantity is not quality, and many sources are bad -- and try putting some more effort into OG and GMATPREP probelms beyond just solving them.
see all the things you can do with these problems here -- read the parts about SC in this thread (from another forum):
http://www.beatthegmat.com/550-to-720-i ... tml#330724

2. "danger of " is the preferred choice just because it is the idiomatic usage. Correct ?

yes.

[saxenankit]

Thanks for the extra prompt reply. It makes sense now.

Yes you are right. I was just browsing the net for SC questions, and I hit this site. I won't do any further questions from this source.

Thanks for the post. I will go through it thoroughly.

______________
Ankit Saxena

[RonPurewal]

sure thing