Ignoring the admonitions of his staff, the chief financial officer acc

BOTH X AND Y ; cor relative conjunction ..
IMO D
he believed that the standardized accounting procedures would prove to beboth inexpensive and

The difference between A and D is that A follows " not only X but Y" form which also appears true and D follows both X and Y form. So why the answer is D and not A?
Or is it because, the correct idiom is "not only X but also Y"
Please help

Ignoring the admonitions of his staff, the chief financial officer accepted the advice of the consulting company because he believed that the standardized accounting procedures would prove not only inexpensive but reliable indicators of economic performance.


(A) he believed that the standardized accounting procedures would prove not only inexpensive but...Procedures would prove inexpensive..Wrong

(B) the standardized accounting procedures will prove both inexpensive and also......Both/Also ...redundant

(C) he believed the standardized accounting procedures would prove themselves to be both inexpensive and.....would prove themselves ..Wrong

(D) he believed that the standardized accounting procedures would prove to be both inexpensive and....Correct

(E) standardized accounting procedures will prove his belief that they are both inexpensive and....Awkward construction

another reasons for elimination is sentence is going from past to conditional , that uses would not will so b and e is out ,in a idiom error so a out , in c pronoun ambiguity/ awkward construction

sentence is in past tense. "CFO believed" is in past so what did he believe should also be in past. Past Future for "Will" is "WOULD"

I think core of sentence will be CFO accepted the advice because he believed that XYZ.

(A) he believed that the standardized accounting procedures would prove not only inexpensive but --- Not Only + But Also. Also is missing here

(B) the standardized accounting procedures will prove both inexpensive and also --- believe is missing.

(C) he believed the standardized accounting procedures would prove themselves to be both inexpensive and--- extra word. I think "believed that" is better than alone believed

(D) he believed that the standardized accounting procedures would prove to be both inexpensive and --- Correct

(E) standardized accounting procedures will prove his belief that they are both inexpensive and --- believe is missing.

[quote="Bunuel"]Ignoring the admonitions of his staff, the chief financial officer accepted the advice of the consulting company because he believed that the standardized accounting procedures would prove not only inexpensive but reliable indicators of economic performance.


(A) he believed that the standardized accounting procedures would prove not only inexpensive but

(B) the standardized accounting procedures will prove both inexpensive and also

(C) he believed the standardized accounting procedures would prove themselves to be both inexpensive and

(D) he believed that the standardized accounting procedures would prove to be both inexpensive and

(E) standardized accounting procedures will prove his belief that they are both inexpensive and[/t

But in D inexpensive is adjective ,reliable factors is noun. How both are parallel.

comparison of A and D:

"not only...but also..." cannot omit any parallel parts! --> "not only inexpensive but reliable indicators" actually omits the "indicators" in the "not only" part. And this is not allowed!

"both... and" can omit parallel parts! --> in D, "both inexpensive and reliable indicators" omits "indicators" in the first part, but this is allowed!

Therefore, D is correct, and A is wrong.


I noticed some people said A is wrong solely based on the fact that "also" is omitted from "not only but also" construction. IMO, it is wrong!! I have seen other OG questions that omits "but" or omits "also" and the sentence is still correct! Therefore, we cannot eliminate A just based on that.
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can you please explain why a is wrong?

Can anyone please help me figure out the antecedent of "he" ?

Is the usage of "he" standard and obvious in the example ?

Thanks in advance.