Heterosexuals in the United States have a significantly lower chance

+1 for B as compared with is use to compare similar/disimilarity between similar objects

for ex He compared his notes with the notes of his friends.

does is the problem in option A.

IMO its A. ...Idiom ... lower..than.

Hey guys its clearly A

B does wrong comparison.

Heterosexuals in the United States have a significantly lower chance of contracting AIDS in comparison with heterosexuals in Sub-Saharan Africa.

lower chance of ........... than chance of heterosexuals in Sub-Saharan Africa would be correct

Chance should be compared with chance

Hope im correct

IMO in A lower ...than is correct but "do" makes this choice worse than "B"
what is the "OA" ?

What does "do" mean in option A. If it is "chance of contracting" then see how the sentence will look lile
Heterosexuals in the United States have a significantly lower chance of contracting AIDS than chance of contarcting heterosexuals in Sub-Saharan Africa.
Now look at option D after rephrasing-

As compared to heterosexuals in Sub-Saharan Africa, Heterosexuals in the United States have a significantly lower likelihood of contracting AIDS.

Correct comparison b/w heterosexuals in Sub-Saharan Africa and Heterosexuals in the United States.
Hence D should be the right answer.

Dear All, thanks for giving a try on this and apologies for delay in posting the OA...

OA:
As pointed out above, this question tests the proper idiom: 'lower... than'. (B) through (D) all do not use the correct idiomatic phrases. (E) has a different problem, one of parallel structure. It uses 'have' and 'those', rather than the correct 'have' and 'do'.

Hi

Could someone please explain why not E. it also has the proper idiom of lower than....

I thought we use 'do' only to mention actions, but have a lower likelihood is a property of a group or race , so why not use 'those;

Apart from the parallelism of “have” and “do”.

“those” does not has a referent (What is “those” referring to).
Here we are comparing “Heterosexuals in the United States” to “heterosexuals in Sub-Saharan Africa”.

Chose A and got convinced with my answer as I kept scrolling down.. Agree with the "lower than" idiomatic explanation..

Yes, it is A. If we erase "do" in option A, then the sentence implies American heterosexuals can somehow contract heterosexuals in Sub-Saharan Africa. This is illogical, as well as vague. The word "do" is essential here.

(A)

Note - "Chance of contracting AIDS" should be compared.

A) a significantly lower chance of contracting AIDS than do
B) a significantly lower chance of contracting AIDS in comparison with
C) a great likelihood of a contracting AIDS more significant than do
D) a significantly lower likelihood of contracting AIDS as compared to
E) a significantly lower chance of contracting AIDS than those[/quote]

No official explanation here and this question appeared in a quiz

Dear Friends,

Here is a detailed explanation to this question-

Meaning is crucial to solving this problem:
Understanding the intended meaning is key to solving this question; the intended meaning of this sentence is that heterosexuals in the United States have a significantly lower chance of contracting AIDS than heterosexuals in Sub-Saharan Africa do.

Concepts tested here: Meaning + Idioms

• "greater" and "lower" must have a logical sequence with "than"; in a comparison, "greater/lower...than" is the idiomatic construction.

A: Correct.
1/ The sentence formed by this answer choice uses the phrases "significantly lower chance" and "than do heterosexuals in Sub-Saharan Africa", conveying the intended meaning - that heterosexuals in the United States have a significantly lower chance of contracting AIDS than heterosexuals, in general, in Sub-Saharan Africa do.
2/ Option A correctly uses the idiomatic construction "lower...than".

B:
1/ This answer choice incorrectly uses the unidiomatic construction "lower...in comparison with"; remember, "greater" and "lower" must have a logical sequence with "than"; in a comparison, "greater/lower...than" is the idiomatic construction.

C:
1/ This answer choice alters the meaning of the sentence through the phrase "great likelihood of contracting AIDS more significant"; the use of the adjectives "great" and "significant" illogically imply that heterosexuals in the United States have a great likelihood of contracting AIDS, and this likelihood is somehow more significant than the likelihood of a contracting AIDS heterosexuals in Sub-Saharan Africa have; the intended meaning is that heterosexuals in the United States have a significantly lower chance of contracting AIDS than heterosexuals in Sub-Saharan Africa do.

D:
1/ This answer choice incorrectly uses the unidiomatic construction "lower...as compared to"; remember, "greater" and "lower" must have a logical sequence with "than"; in a comparison, "greater/lower...than" is the idiomatic construction.

E:
1/ The sentence formed by this answer choice alters the meaning of the sentence through the phrase "those heterosexuals in Sub-Saharan Africa"; the construction of this phrase incorrectly implies that heterosexuals in the United States have a significantly lower chance of contracting AIDS than a certain subset of heterosexuals in Sub-Saharan Africa does; the intended meaning is that heterosexuals in the United States have a significantly lower chance of contracting AIDS than heterosexuals, in general, in Sub-Saharan Africa do.

Hence, A is the best answer choice.

All the best!
Experts' Global Team