OG Gmat Review 11th edition Sentence Correction # 134

[resilient]

Recently implemented "shift worker equations" based on studies of the human sleep cycle have reduced sickness,sleeping on the job, fatigue among shift workers, and have raised production efficiency in various industries.

a. same
b. fatigue among shift workers, and raised
c. and fatigue among shift workers while raising
d. lowered fatigue among shift workers, and raised
e. and fatigue among shift workers was lowered while raising

I chose A because the original sentence said HAve REduced ..so I chose A because it has HAS RAISED in it to match the original.
the correct choice is C . even though it has raising in the end. I am lost on the verb tense of this matter. Can anyone help?

[Stuart@KaplanGMAT]

Recently implemented "shift worker equations" based on studies of the human sleep cycle have reduced sickness,sleeping on the job, fatigue among shift workers, and have raised production efficiency in various industries.

a. same
b. fatigue among shift workers, and raised
c. and fatigue among shift workers while raising
d. lowered fatigue among shift workers, and raised
e. and fatigue among shift workers was lowered while raising

As soon as you see a list of items, think parallelism.

Here we have both a list and a contrast - the new equations have reduced 3 things and raised 1 other. We need to keep the two parts of the sentence separate.

Let's start with our list of factors that were reduced: we want the list to read "reduced a, b and c". The original sentence is missing the "and" in the list, so eliminate (a). The only choices that include the "and" required are (c) and (e), so also elminate (b) and (d).

(e) includes "was lowered" at the end of the list, which is redundant to "reduced". Eliminate (e).

Only one choice left: choose (c) (which includes the contrast keyword "while", another thing we would have looked for if we didn't already know that (c) were correct).

[ashish1354]

and fatigue among shift workers while raising = Correct answer

OG explanation suggests that while raising emphasizes contrast with have reduced.

although William Strunk, Jr., the author of The Elements of Style clearly states in his book

While. Avoid the indiscriminate use of this word for and, but, and although. Many writers use it frequently as a substitute for and or but, either from a mere desire to vary the connective, or from uncertainty which of the two connectives is the more appropriate. In this use it is best replaced by a semicolon.

In general, the writer will do well to use while only with strict literalness, in the sense of during the time that.

i am lost! Can someone clear the air? what do we chose when "while" turns up
contrast or simultaneous action?