Sentence Correction

Represented by widening income and standard of living gaps, increasing economic disparity, when exacerbated simultaneously by population growth, often leads to social unrest and rioting.

A. when exacerbated simultaneously by population growth, often leads
B. when exacerbated by simultaneously grown population, often lead
C. when being exacerbated by simultaneous growth in population, often leads
D. if exacerbated simultaneously by population growth, often lead
E. if exacerbated by simultaneous population growth, often leads

Could anyone please tell me when to use"WHEN" and when to use IF....

This is one of the cases where if and when are both grammatically correct, and you must decide based on the meaning and logic of the sentence.

If refers to a condition, so it would be more relevant in a prediction, e.g., talking about specific economic disparity and what it might lead to; this would require the final part to be in the future tense:

...(this country's) economic disparity, if exacerbated simultaneously by population growth, will lead to social unrest and rioting.

When refers to a correlation in time, and hence is used for general truths (when you do A, you get B). This sits well with the present simple tense, which also deals with general truths and facts:

...(in general) economic disparity, when exacerbated simultaneously by population growth, often leads to social unrest and rioting.

The toss-up is between A and E (B and D have subject-verb mistakes, and C is wordy and awkward). Since E has if followed by often, mixing prediction with general truth, A is preferable.

psychomath wrote:Represented by widening income and standard of living gaps, increasing economic disparity, when exacerbated simultaneously by population growth, often leads to social unrest and rioting.

A. when exacerbated simultaneously by population growth, often leads
B. when exacerbated by simultaneously grown population, often lead
C. when being exacerbated by simultaneous growth in population, often leads
D. if exacerbated simultaneously by population growth, often lead
E. if exacerbated by simultaneous population growth, often leads

Could anyone please tell me when to use"WHEN" and when to use IF....

When Vs If


When or if?
We use when for things that are certain to happen in the future:

I'll buy you a pair of gloves when I go shopping this afternoon.
I'll give you a ring when I get home from school.
Note that although the reference is clearly to the future, we use the present tense in the when-clause.

We use if for things that may happen and which we are not certain about:

If I decide to come to London this year, I'll come and visit you.

I'm going to call the police if she's not back within the hour.

If you make the salads, I'll prepare the barbecue.
In all of these examples, we are talking about future conditions and whether we use when or if depends upon the certainty of things happening.

However, when and if are interchangeable when we are talking about general conditions that always apply when if means almost the same as whenever. Compare the following:

I keep the air-conditioning on at night if the temperature goes above 30 degrees.

I keep the air-conditioning on at night whenever / when the temperature goes above 30 degrees.

If the green flag is flying, it's quite safe to swim here
You can swim here whenever / when / provided the green flag is flying.

Now, come to the problem.

We don't know the result. So, we are required to use if.

Answer is E.

@ gmat_perfect
E violates the idiom if ..then construction
if(past)......then(wud or wud have) is correct idiom
but any way thanks for highlightening the diff

OA Must be A.....could someone please confirm ?

Thanks a ton guys....BTW OA is E

I chose A for this...Source is GROCKIT

IMO A

Represented by widening income and standard of living gaps, increasing economic disparity, when exacerbated simultaneously by population growth, often leads to social unrest and rioting.

A. when exacerbated simultaneously by population growth, often leads
B. when exacerbated by simultaneously grown population, often lead
C. when being exacerbated by simultaneous growth in population, often leads
D. if exacerbated simultaneously by population growth, often lead
E. if exacerbated by simultaneous population growth, often leads

Split:
Leads / Lead : - Subject "economic disparity" is singular so leads. B & D out
Being : Mostly not preferable in GMAT

Down TO A and E : Apart from When vs if we can also look at phrase attached to when / if:

E: exacerbated by simultaneous population growth --Changes meaning of original sentence . now "simultaneous" incorrectly modify "population growth"

A: exacerbated simultaneously by population growth - Correct