SC:Although no proof yet exists of

[jjykim]

Although no proof yet exists of electromagnetic fields generated by household appliances posing any health threat, mounting scientific evidence has convinced many experts that there is cause for concern.
(A) of electromagnetic fields generated by household appliances posing any health threat
(B) of electromagnetic fields generated by household appliances that pose any threat to health
(C) that electromagnetic fields generated by household appliances pose any threat to health
(D) that poses any threat to health from electromagnetic fields generated by household appliances
(E) for any health threat posed by electromagnetic fields generated by household appliances

the correct answer is C but could someone please explain why?

[jjykim]

Although no proof yet exists of electromagnetic fields generated by household appliances posing any health threat, mounting scientific evidence has convinced many experts that there is cause for concern.

[RonPurewal]

you probably picked answer choice (a), but i'll give a brief treatment of all of them, just to be sure.

(a)
you cannot write "proof of ... fields ... posing".
sorry.
this is going to annoy a lot of people, because this sort of construction is bread and butter in spoken language,
BUT:
if the focus of the construction is the ACTION, then you must use the POSSESSIVE form for the noun/pronoun preceding the "-ing" participle. since that's fatally awkward to say in words, i'll provide an example:
everyone laughed at me accidentally walking into the girls' bathroom --> WRONG. sorry. this sentence would actually mean that everyone laughed at me as they were walking into the girls' bathroom.
everyone laughed at my accidentally walking into the girls' bathroom --> CORRECT, because it's the action (my walking into the bathroom, not really me) that they're laughing at.

so, incredibly enough, the correct version of the sentence here would actually be "the fields' posing ...". but then you just have bad writing (for stylistic reasons, which aren't tested here).

incidentally, if the focus of the construction is the NOUN (or pronoun) itself, then you don't use a possessive. for instance:
i saw him walking down the street --> correct, because it was him i saw, not his walking action. (in SPOKEN english, this sentence is ambiguous, because either he or i may have been the one walking down the street. in formal written english, though, he's the one walking.)
i saw his walking down the street wouldn't be incorrect, but it would be a bit strange, unless i'm a modeling scout who actually analyzes the gait of random strangers as they walk down the street.

[RonPurewal]

other wrong choices:

(b)
"...that pose any threat to..." is a modifier, so this sentence is actually saying that there's no proof of the existence of the electromagnetic fields themselves. that's not what it's supposed to say.

(d)
according to the wording of this one, the proof itself would pose a health threat. that's obviously absurd.

(e)
"proof for" is unidiomatic; the correct idiom is "proof of".

[dps]

And I think "posing any health threat" in A and "that pose..." in C have ambiguous reference
It can be either for household appliances or electromagnetic fields

Is that correct?

[RonPurewal]

And I think "posing any health threat" in A and "that pose..." in C have ambiguous reference
It can be either for household appliances or electromagnetic fields

Is that correct?

try reading choice (c) more closely: it just says "pose", NOT "that pose".
per the conventions of subject-verb agreement, we ignore the modifier (generated by household appliances) and designate "electromagnetic fields" as the subject of the verb "pose".
in fact, choice (c) wouldn't even be a sentence if it said "that pose", because there's already a "that" preceding "electromagnetic fields". try writing out the whole sentence the way you originally misread it (with the two "that"s) and see what i mean.

therefore, (c) is just fine.

hth

[dps]

What about "posing any health threat" in A? Is that ambiguous?

[RonPurewal]

What about "posing any health threat" in A? Is that ambiguous?

probably not. when an "-ing" modifier is NOT preceded by a comma, it's generally taken to modify the noun that immediately precedes it.
from what we've seen, the gmat is generally in accord with this standard.

[navdeep_bajwa]

Although no proof yet exists of electromagnetic fields generated by household appliances posing any health threat, mounting scientific evidence has convinced many experts that there is cause for concern.
(A) of electromagnetic fields generated by household appliances posing any health threat
(B) of electromagnetic fields generated by household appliances that pose any threat to health
(C) that electromagnetic fields generated by household appliances pose any threat to health
(D) that poses any threat to health from electromagnetic fields generated by household appliances
(E) for any health threat posed by electromagnetic fields generated by household appliances

Can you please explain the difference between A & B
Is "that" in B modifying "electromagnetic fields" then why and why not "appliances"
Also in A what is posing modifying "electromagnetic fields" then why and why not "appliances"

Also is that and which can modify only singular nouns and ING modifies both singular and plural

[navdeep_bajwa]

what is "that" modifying in B

[RonPurewal]

Can you please explain the difference between A & B
Is "that" in B modifying "electromagnetic fields" then why and why not "appliances"
Also in A what is posing modifying "electromagnetic fields" then why and why not "appliances"

both (a) and (b) are wrong answers; it's unwise to plumb incorrect answers for grammatical patterns.

also, if you read the posts above, you'll see that we've already had an extensive discussion of "posing" in (a).

since (b) is not correct, the only thing with which you should really concern yourself is finding the intended antecedent, i.e., "that" is intended to stand for "fields".

Also is that and which can modify only singular nouns and ING modifies both singular and plural

no, both "that" and "which" can be used for either singular or plural nouns.

[navdeep_bajwa]

Ron Can you please explain what you mean by this

if the focus of the construction is the ACTION, then you must use the POSSESSIVE form for the noun/pronoun preceding the "-ing" participle.

Everyone laughed at my accidentally walking into the girls' bathroom
Here the focus is on "my accidentally walking into the girls' bathroom " I mean the focus is on ing

In the original problem how the focus is on "posing health threat" and not "electromagnetic fields"

[RonPurewal]

Ron Can you please explain what you mean by this

if the focus of the construction is the ACTION, then you must use the POSSESSIVE form for the noun/pronoun preceding the "-ing" participle.

Everyone laughed at my accidentally walking into the girls' bathroom
Here the focus is on "my accidentally walking into the girls' bathroom " I mean the focus is on ing

In the original problem how the focus is on "posing health threat" and not "electromagnetic fields"

if you think about the context, this should become clear. the sentence starts out with "no evidence yet exists of..."
... so, ask yourself: WHAT don't we have evidence of yet?
* we don't yet have evidence of the electromagnetic fields themselves? --> nope, that doesn't make any sense
* we don't yet have evidence of their posing a threat? --> yes, this makes more sense

[mcmebk]

you probably picked answer choice (a), but i'll give a brief treatment of all of them, just to be sure.

(a)
you cannot write "proof of ... fields ... posing". this kind of construction is just wrong.
sorry.
this is going to annoy a lot of people, because this sort of construction is bread and butter in spoken language,
BUT:
if the focus of the construction is the ACTION, then you must use the POSSESSIVE form for the noun/pronoun preceding the "-ing" participle. since that's fatally awkward to say in words, i'll provide an example:
everyone laughed at me accidentally walking into the girls' bathroom --> WRONG. sorry. this sentence would actually mean that everyone laughed at me as they were walking into the girls' bathroom.
everyone laughed at my accidentally walking into the girls' bathroom --> CORRECT, because it's the action (my walking into the bathroom, not really me) that they're laughing at.

so, incredibly enough, the correct version of the sentence here would actually be "the fields' posing ...".
the gmat normally considers such constructions fatally awkward, and won't include them in correct answers (i believe this has been articulated in the official guide at a couple of different points, so i'm not just making an empirical claim). therefore, you can ignore such constructions outright, and eliminate choices that contain them.

incidentally, if the focus of the construction is the NOUN (or pronoun) itself, then you don't use a possessive. for instance:
i saw him walking down the street --> correct, because it was him i saw, not his walking action. this sentence is, however, ambiguous, because either he or i may have been the one walking down the street.
i saw his walking down the street wouldn't be incorrect, but it would be a bit strange, unless i'm a modeling scout who actually analyzes the gait of random strangers as they walk down the street.

Hi Ron

would you please kindly clarify "the gmat considers such constructions fatally awkward, and won't include them in correct answers", which construction do you mean? the of+Sbject+Ving or of+Sb's+V-ing construction?

Thank you.

[RonPurewal]

Hi Ron

would you please kindly clarify "the gmat considers such constructions fatally awkward, and won't include them in correct answers", which construction do you mean? the of+Sbject+Ving or of+Sb's+V-ing construction?

Thank you.

the latter, since that's the construction under discussion where that comment is located. sorry if that was unclear.

the former construction is actually wrong, not just awkward, in the type of context that i described.