Machines powered by hydraulics are not driven by the steam

In this sentence the logic is "in place of x, y does something". Please note that in such cases where x is replaced by y, "instead" is correct ; but in cases where x is prefferred over y, "rather" is used.
Moreover, no contast given by "but" is needed here. There is just a replacement.
The two clauses separated apart by ";" are purely independent. To separate such clauses, either ", + conjuncting verb" or "; instead" is preferred. But since there is no need of "but" here, hence only correct option is C.

Neither the prepositional phrase ‘rather than’ nor ‘instead of’ is part of the choices in the issue. Only rather and instead are the issues. Hence, I feel there is no need to confuse with unmentioned choices here. . The thing to note is that that an independent but somewhat related clause should follow a semicolon.

Choices A and B fall out because of the redundant use of ‘but rather’ and ‘but instead’. Among the adverbs -instead and rather - and the conjunction ‘but, IMO, ‘instead’ fits into the groove better because of the precise meaning of “in that place” which is better than mere contrast markers such as ‘rather and but’

C is a winner by a whisker
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Choices A and B fall out because of the redundancy of ‘but rather’ and ‘but instead’. Among the adverbs -instead and rather - and the conjunction ‘but, IMO, ‘instead’ fits in the groove better because its precise meaning “in the place” fits in smugly over the contrast - markers,-- but and rather.--

C is a winner by a whisker
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Hey - Opion D "; rather" - Are there any grammatical reasons for which we can eliminate this option.
Consider the below sentence.

I will get my car rims finished in Matt grey rather in black
I will get my car rims finished in Matt grey instead of black.

both seem right.

Cheers

Hi JP 27

I think the later one is correct, you can not use rather fro noun
black and matt grey both are noun, hence you have to use instead.

Moreover, you are choosing black over matt grey ie.. you are replacing.
hence instead to be used.

Hii JP.
IMO both sentences are grammatically correct. Meaning wise, the intent is changing.
In 1) you prefer Matt grey over black
In 2) you just wanna replace Matt grey with black.
Hope that helps.

you mean to say we use instead for replacement and rather for preferences,,,plz clear it to me thanks

Yes.
Use Instead for replacement and rather for preference.
Also note that if there is "instead of", then make sure that "instead of" is followed by a noun. It is so because "of" is a preposition and all prepositions are followed by a noun.
Hope that helps.

I am unable to comprehend as to why A is incorrect.

Views, please?

Machines powered by hydraulics are not driven by the steam produced by boiling water, but rather,
high-pressure fluids are transmitted throughout the machine to various motors and hydraulic cylinders.

a) water, but rather
b) water, but instead
c) water; instead
d) water; rather
e) water; but

Both options A and B are wrong due to redundancy issues ie but and rather BOTH show contrast , so only one of them is needed.
similarly instead and but have the same problem

AND instead is preferred to Rather here bcoz instead stands for replacement of one thing for another (high-pressure fuilds for steam) whereas rather stands for a choice b/w 2 alternatives or things. So it is C

Hope it is clear.

In MGMAT SC Chapter-9, Idiom : NOT..BUT, but rather and but instead are used in correct sentences.
e.g. A tomato is not a vegetable BUT RATHER a fruit.

I know in this question we need a coordinating conjunction to join two independent clause or ; , but making a claim that but instead or but rather together are redundant is challenging usage as mentioned in above stated example. Could anyone please help to clarify when it will be redundant and when it is ok ?

souvik101990
mikemcgarry
carcass

Instead should be followed by a noun phrase right??
THen how come choice c is Right.
Here the right usage should be rather??

Why should 'instead' be followed by a noun phrase? After all, 'instead' is not a preposition; 'instead of' only is a prepositional phrase and must be followed by a noun or a noun phrase. Instead simply means 'in that place'

'Rather' is used when we wish to show some discrimination or preference favoring one over another. When such preference is absent, it is ok to use 'instead', IMO. In the given case no preference for use of high-pressure fluids is shown over steam. It is just that hydraulic machines use a particular process compared to the other type of machines.
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But/rather/ but rather all demands parrallel structures. Instead is a complex preposition so it can forego parallel rules

OFFICIAL EXPLANATION

Correct Answer: C

This sentence is connecting two independent clauses and so needs a conjunctive connector or semicolon to link the two. Answer (E) can be eliminated for redundantly using both a semicolon and the conjunction "but". Additionally, the meaning of the contrasting conjunction "but" is incorrect here; the contrast this sentence draws between hydraulic machines and steam-powered machines is more appropriately illustrated with the adverb "instead". Answers (A) and (B) can be eliminated for using "but." Answer (D) can be eliminated for using the ambiguous adverb "rather", which may be modifying the adjective "high-pressure" or the verb "are transmitted". Additionally, "rather" expresses a preference for one choice over another; the idiomatic "instead" is a better fit, leaving (C) as the correct answer.
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C -for me. Most succinct in meaning and clause construction

Machines powered by hydraulics are not driven by the steam produced by boiling water, but rather, high-pressure fluids are transmitted throughout the machine to various motors and hydraulic cylinders.

a) water, but rather - there should be a 'by' 'but rather by' - cause we are connecting two processes
b) water, but instead - but instead; are two words with two tonal indications- but indicating contrast and instead, indicating an alternative - very slight difference, but it exists
c) water; instead - seems valid. Following semi colon, we have the complete independent clause (appropriately after semicolon and 'instead'). Sentence would read as "water; INSTEAD, high-pressure fluids are transmitted throughout the machine to various motors and hydraulic cylinders.)
d) water; rather - incorrect tone
e) water; but - incorrect word, there is no contrast, as such

Hope it is C!

This question seems to be inspired from an official question https://gmatclub.com/forum/the-energy-source-on-voyager-2-is-not-a-nuclear-reactor-in-which-atom-47316.html, in which the correct answer uses the phrase "but rather". I don't understand why we are eliminating option A based on redundancy use. The official question doesn't seem to think this way

“but rather” and “but instead” are both redundant. So, A and B are probably not the right options.We can judge the remaining choices on the basis of their comparatives. I am going to say that C is the best choice because “instead” ( which means ‘this not that’ )best fits the meaning that this sentence is trying to convey.