Visualization of mental images is a central concept in the Bates method—s
omething not only which could achieve a state of inner balance and relaxation, but improving focus, eye coordination, blood circulation, and eye movement control.
(A) something
not only which could achieve a state of inner balance and relaxation,
but improving
--Not only X but also Y is the correct idiom where X and Y should be parallel.
--Not only X but Y denotes contrast. The intended meaning here is not to show contrast
(B) something which not only
could achieve a state of inner balance and relaxation, but also
to improve --Not only X but also Y is the correct idiom where X and Y should be parallel.
--X = could achieve ..... Y = to improve. These 2 are not parallel.
(C) something which could not only achieve a state of inner balance and relaxation, but also improve
CORRECT(D)
that being something which could not only
achieve a state of inner balance and relaxation, but also
improving --"that being" has no role here.
--Not only X but also Y is the correct idiom where X and Y should be parallel.
--X = achieve ..... Y = improving. These 2 are not parallel.
(E) being something not only which could achieve a state of inner balance and relaxation, but improve
--"being" has no role here. It does not add any value
--Not only X but also Y is the correct idiom where X and Y should be parallel.
--X = which could achieve Y = improve. NOT parallel.
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