First of all please post the questions in their relevant forums, so that you may get esponses quite fast.
Coming to the question, the parallelism is shown in could lead to and decrease the probablity.
I doubt the paralleism is shown in lead to x and Y.

paes wrote:The proposal by the federal government to bail out two of the nation's largest lending institutions could lead to greater market stability and decreasing the probability of worldwide economic recession.
(A) decreasing the probability
(B) the probability decreased
(C) the probability decreasing
(D) the decreasing of probability
(E) decrease the probability

[spoiler]OA : E
I am confuse between D and E. It should be, could lead to X and Y. X refers to 'market stability' - Noun
but in E - 'decrease the probability' , decrease is a verb.
Please clarify how the two are parallel[/spoiler]

First of all, you posted your question on a wrong place. So, be careful next time!!!

Second, to answer your question. answer D is wrong because it uses the decreasing instead of decrease. Decrease is not only a verb, but also a Noun. So, if the author wants to use decrease as a noun, he should use decrease not decreasing. That's why answer D, wrong.

bupbebeo wrote:

paes wrote:The proposal by the federal government to bail out two of the nation's largest lending institutions could lead to greater market stability and decreasing the probability of worldwide economic recession.
(A) decreasing the probability
(B) the probability decreased
(C) the probability decreasing
(D) the decreasing of probability
(E) decrease the probability

[spoiler]OA : E
I am confuse between D and E. It should be, could lead to X and Y. X refers to 'market stability' - Noun
but in E - 'decrease the probability' , decrease is a verb.
Please clarify how the two are parallel[/spoiler]

First of all, you posted your question on a wrong place. So, be careful next time!!!

Second, to answer your question. answer D is wrong because it uses the decreasing instead of decrease. Decrease is not only a verb, but also a Noun. So, if the author wants to use decrease as a noun, he should use decrease not decreasing. That's why answer D, wrong.

Yes, I tried to move/delete the question, but could not know how to do it. Sorry for it.
taking decrease as a noun, E is correct.
But in D, 'the decreasing' is also a gerund noun, so why it is incorrect.

This one throws a very interesting curve ball. As varying interpretations among the previous posts suggest, there actually IS some ambiguity about what must be parallel. Without the answer choices to guide us, we're not sure if we're looking at:

"... could lead ... and verb ..."

or

"... could lead to stability ... and noun ..."

Answer choice (E) gives us a verb that is parallel with the verb "lead" and a complete sentence written in clear, concise style.

Answer choice (D) does give us a noun/gerund form of "decreasing" ... but how do we know it's wrong? Style must win out here. When offered an answer choice that relies on an unnecessary gerund construction, and another EQUALLY CORRECT answer choice is available, the latter tends to be correct. This is certainly not a hard and fast rule, but it's a great guideline.

Notice that a more desirable noun form, such as "a decrease in the probability," was not offered as a choice, although as bupbebeo points out, that would be correct and much better stylistically.

Hope that helps!

stephen@knewton wrote:This one throws a very interesting curve ball. As varying interpretations among the previous posts suggest, there actually IS some ambiguity about what must be parallel. Without the answer choices to guide us, we're not sure if we're looking at:

"... could lead ... and verb ..."

or

"... could lead to stability ... and noun ..."

Answer choice (E) gives us a verb that is parallel with the verb "lead" and a complete sentence written in clear, concise style.

Answer choice (D) does give us a noun/gerund form of "decreasing" ... but how do we know it's wrong? Style must win out here. When offered an answer choice that relies on an unnecessary gerund construction, and another EQUALLY CORRECT answer choice is available, the latter tends to be correct. This is certainly not a hard and fast rule, but it's a great guideline.

Notice that a more desirable noun form, such as "a decrease in the probability," was not offered as a choice, although as bupbebeo points out, that would be correct and much better stylistically.

Hope that helps!

what if we had an option "decreased probability".
->could lead to greater stability and decreased probability of recession

I would have taken E as 'decreasing' breaks the parallelism...
and in D ,
ing of ...of is making it wordy (they will say so)

and if i have to consider in that ground(verb and all...),i see that even A is better than D

so E wins here
to parallel simple verbs

parallelism to maintain between lead to greater market stability and decrease the probability of worldwide economic recession

hence E is correct choice

if it is leading to........then we need decreasing of probability then D would be correct.

stephen@knewton wrote:This one throws a very interesting curve ball. As varying interpretations among the previous posts suggest, there actually IS some ambiguity about what must be parallel. Without the answer choices to guide us, we're not sure if we're looking at:

"... could lead ... and verb ..."

or

"... could lead to stability ... and noun ..."

Answer choice (E) gives us a verb that is parallel with the verb "lead" and a complete sentence written in clear, concise style.

Answer choice (D) does give us a noun/gerund form of "decreasing" ... but how do we know it's wrong? Style must win out here. When offered an answer choice that relies on an unnecessary gerund construction, and another EQUALLY CORRECT answer choice is available, the latter tends to be correct. This is certainly not a hard and fast rule, but it's a great guideline.

Notice that a more desirable noun form, such as "a decrease in the probability," was not offered as a choice, although as bupbebeo points out, that would be correct and much better stylistically.

Hope that helps!

thanks Stephen.

You're very welcome!

To answer a follow-up question that's been raised, "decreased probability" would indeed also be a good alternative, if it were among the answer choices ...

... HOWEVER ... this might be a good excuse to share some cautionary test-taking advice for SC: "pre-phrasing" or coming up with a "better" way to word a sentence can be dangerous! I've already done it once myself in this thread, and I'll even use it in class because it's a good tool to help us understand the grammatical rules, as we are doing here. But make sure you do NOT get into the habit of doing this on the test. On the test, focus your energy on ELIMINATION. As we've seen here, you might come up with several "correct" ways to re-write a sentence, only to find that none of them is among the answer choices!

Cheers,