1.'children's cancer' is incorrect as it seems to be a type of cancer of children which is u idiomatic, correct form is 'cancer among children'
2. Since there is 'than' in noon underlined portion and we are comparing number of cases (countable nouns) 'more' is correct

(A) children's cancer, and altered birth ratios of males and females are much higher -1,2
(B) cancer among children, and altered male and female ratios at birth are much higher -2 and also phrase 'altered male and female ratios at birth' is incorrect as sentence wants to highlight 'altered birth ratios of males and females'
(C) cancer among children, and altered birth ratios of males and females occur much more frequently - Correct
(D) altered birth ratios of males and females, and children's cancer are much higher -1,2
(E) altered male and female ratios at birth, and cancer among children occur much more- same error as discussed in B.

Hence C

Posted from my mobile device

We are looking for "occur", as it sounds weird to say "cancer among children" is much higher.

Thus, we are left with a&c and c looks to be the idiomatically correct choice.

However, I think there might be a typo in the OS "have found other besides miners and mill workers to be affected"

I guess the highlighted should be others?

Best regards,
Chris
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Statisticians studying the health effect of uranium mining on Navajo communities have found other besides miners and mill workers to be affected; birth defects, children's cancer, and altered birth ratios of males and females are much higher in mining than in non-mining communities.

The sentence has two independent clauses separated correctly. We have a list of problems that occur in underlined part. This list has to be parallel and logical.

(A) children's cancer, and altered birth ratios of males and females are much higher (children's cancer, and altered birth ratios of males and females, Possessive noun and non-possessive noun - incorrect.)
(B) cancer among children, and altered male and female ratios at birth are much higher (altered male and female ratios at birth? Male:Female are not altered at birth, their birth ratios are altered. Incorrect)
(C) cancer among children, and altered birth ratios of males and females occur much more frequently (Correct)
(D) altered birth ratios of males and females, and children's cancer are much higher (same error as in A)
(E) altered male and female ratios at birth, and cancer among children occur much more (same error as in B)

Official Explanation

Diction; Logical predication

Statisticians have been studying the frequencies of various health outcomes in uranium mining areas in Navajo communities. They have found that certain kinds of bad outcomes occur much more frequently in mining communities than in non-mining communities.

We need to pick the answer choice that best expresses this finding. The use of the predicate higher is appropriate when applied to rates of illness. However, it is not appropriate when applied to medical conditions (except as an informal shorthand), e.g., a claim that birth defects . . . are much higher. That is, it is unclear what a higher birth defect might specify.

The meaning of altered male and female ratios is unclear, as opposed to altered birth ratios of males and females.

A. In this choice, the statement altered birth ratios . . . are much higher is unclear.

B. In this choice, the statement altered . . . ratios at birth are much higher is unclear.

C. Correct. The idea of the sentence is expressed clearly and the phrase occur much more frequently clearly specifies altered birth ratios.

D. In this choice, it is unclear what is higher: it could be birth ratios of males and females, children's cancer, or both.

E. In this choice, the modifier at birth implies, nonsensically, that the ratios were altered at the time of birth. Furthermore, male and female ratios implies that the ratios themselves are of male or female gender.

The correct answer is C.

Really 've taken too much time to solve it ( 3.18 sec ) and then made it wrong eventually like I always do whenever I take too much ..T..
was in a bit of quandary for choosing the correct option among...
cancer among children sounds good compared to children's cancer
altered birth ratios of males and females sounds better than altered male and female ratios at birth,
but for option C everything seems okay and even better than others by using occur but Does it sound good by using Double superlative much more frequently ?

Please clarify about this for option C ?
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Statisticians studying the health effect of uranium mining on Navajo communities have found other besides miners and mill workers to be affected; birth defects, children's cancer, and altered birth ratios of males and females are much higher in mining than in non-mining communities.

(A) children's cancer, and altered birth ratios of males and females are much higher
(B) cancer among children, and altered male and female ratios at birth are much higher
(C) cancer among children, and altered birth ratios of males and females occur much more frequently
(D) altered birth ratios of males and females, and children's cancer are much higher
(E) altered male and female ratios at birth, and cancer among children occur much more

The best way I found to solve this question is that there is a comparison between mining and non-mining communities.
So for comparison, there must be some comparison word such as more, less, smaller, etc
Now if you go through options ....You will find "more" for comparison in option C and E.
Option C seems more appropriate.
Hope this helps

daagh

Sir, would you consider it redundant to say "much more frequently"?
I know it is a GMAC question, but as the meaning issue was very hard to resolve I ditched C) because I thought this showed clear redundance issues.
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I wouldn't think so. 'Much' is an intensifier and 'more' is a comparator.The use of much is to say that the frequencies are happening in shorter intervals, whereas 'more' simply may mean that the total number is more than in one place than in the the other areas.
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(A) children's cancer, and altered birth ratios of males and females are much higher
- Children do not possess/own cancer - incorrect
- Use of "are" - correct
- Wrong

(B) cancer among children, and altered male and female ratios at birth are much higher
- "altered male and female ratios at birth" seems to suggest that a baby is x% female and y% male
- Wrong

(C) cancer among children, and altered birth ratios of males and females occur much more frequently
- Correct reference of cancer and birth rations
- Correct

(D) altered birth ratios of males and females, and children's cancer are much higher
- Children's cancer - wrong
- incorrect

(E) altered male and female ratios at birth, and cancer among children occur much more
- ratios at birth - wrong
- incorrect

If the answers is c..then it means..altered birth ratios of male and female occur..how can a ratio occur..its not a phenomenon..cancer can occur,child defects can occur..but ratios..it doeant make sense to me..what u guys think?

Posted from my mobile device

Subject - Verb Agreement

In Summary

(A) children's cancer, and altered birth ratios of males and females are much higher ----- "are much higher" as a verb does not logically agree with the first two elements of the list: DEFECTS and CANCER. Additionally, "children's cancer" is wrong as the CANCER does not BELONG to the children.
(B) cancer among children, and altered male and female ratios at birth are much higher ----- "are much higher" as a verb does not logically agree with the first two elements of the list: DEFECTS and CANCER.
(C) cancer among children, and altered birth ratios of males and females occur much more frequently ---- CORRECT
(D) altered birth ratios of males and females, and children's cancer are much higher ----- "are much higher" as a verb does not logically agree with the elements of the list: DEFECTS and CANCER.
(E) altered male and female ratios at birth, and cancer among children occur much more ---- Wrong meaning. "ratios at birth" is wrong, since we are trying to say "birth ratios"
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Dear Friends,

Here is a detailed explanation to this question-



Choice A: Option A uses the phrase "children's cancer", which is quite awkward as it implies a type of cancer exclusive to children. Moreover, this answer choice utilizes the word "higher" to refer to an uncountable noun, "rates". Thus, Option A is incorrect.

Choice B: Option B commits the same error with regards to the word "higher", seen in Option A. Thus, Option B is incorrect.

Choice C: Option C is quite concise and uses the proper term "more" to denote the level of occurrences. Thus, Option C is correct.

Choice D: Option D displays the same errors that Option A does. Thus, Option D is incorrect.

Choice E: Option E also utilizes the awkward and inaccurate phrase "children's cancer". Thus, Option E is incorrect.

Hence, C is the best answer choice.

To understand the concept of “Collective, Countable, and Uncountable Nouns on GMAT”, you may want to watch the following video (~2 minutes):



All the best!
Experts' Global Team
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GMATNinja

I'm keen to see your analysis of this question.
Thanks in advance!

When you see the phrase ‘children’s cancer’ you should get the sense that all is not right here.

Quickly scan the options to see the alternatives that are provided.

‘cancer among children’ seems clear and elegant.

In Options A and B, you also notice that ‘higher’ is the wrong choice of word here.

Eliminate Options A and B.

Let’s move on to Options D and E.

Option D has ‘higher’ alongside ‘ratios’ – Eliminate.

Option E has ‘at birth’ which alters the meaning. Eliminate.

Option C is the best choice.

Hope this helps!
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altered birth ratios … are much higher is unclear.
- is this because, its like saying 'much higher then what exactly?'

Dear GMATGuruNY

Can you help please with the above question?

1- is the usage of ' much higher' idiomatic or should be only 'more higher' ?

2- Why usage of higher here is wrong? 'ratios' are numbers so I can use 'higher' here. Or should be 'greater'? Is not the same as this example: the price of Mercedes is higher the price of Toyota

Thanks in advance

much higher is correct.
more higher is redundant and thus is incorrect.
On its own, -ER implies MORE.



Birth defects, children's cancer, and altered birth ratios are much higher in mining than in non-mining communities.
Here, the portion in blue serves as the subject for are.
Conveyed meaning:

Birth defects are higher in mining communities than birth defects are high in non-mining communities.
This meaning is nonsensical, since a DEFECT cannot be HIGH.

Cancer is higher in mining communities than cancer is high in non-mining communities.
This meaning is nonsensical, since CANCER cannot be HIGH.

Altered birth ratios are higher in mining communities than altered birth ratios are high in non-mining communities.
Implication:
Birth ratios are altered in BOTH types of communities.
The altered birth ratios in mining communities are HIGHER.
The statement in red seems unintended.
The following meaning seems more likely:
Altered birth ratios in non-mining communities are RARE.
Altered birth ratios in mining communities are FAR MORE COMMON.
This meaning is conveyed by the OA:
Altered birth ratios OCCUR MUCH MORE FREQUENTLY in mining than in non-mining communities.
Implied comparison:
Altered birth ratios occur much more frequently in mining communities than altered birth ratios occur in non-mining communities.
In other words:
Altered birth ratios in non-mining communities are RARE.
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I used PoE to solve this one
1. Children's cancer vs cancer among children - the former means a type of cancer which happens to children, latter conveys the correct meaning
Options A and D - ELIMINATED

2. altered birth ratios of males and females vs altered male and female ratios at birth
Former is correct because at the birth this ratio is altered?? means something very different from what author is trying to convey
Options B and D - ELIMINATED

Thus, Option C is the correct answer

Why "HIGHER" is wrong in option B.
Kindly explain in details. Thanks!
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