Sentence Correction

Performing a risky maneuver that required precision flying, not only did space shuttle astronauts retrieve an orbiting satellite, it was done simultaneously while avoiding being rear-ended by a passing ultraviolet telescope.
A. not only did space shuttle astronauts retrieve an orbiting satellite, it was done simultaneously while avoiding
B. not only was an orbiting satellite retrieved by space shuttle astronauts, but they also simultaneously avoided
C. an orbiting satellite was retrieved by space shuttle astronauts who also avoided simultaneously
D. space shuttle astronauts retrieved an orbiting satellite, simultaneously while avoiding
E. space shuttle astronauts retrieved an orbiting satellite and simultaneously avoided

my concern: i can pick E as correct answer; however, i want to know something about option D. is option D wrong just because "simultaneously while" is redundant?
i want to know whether following (modified D) would be correct: space shuttle astronauts retrieved an orbiting satellite, while avoiding
OR will be wrong because "comma+ while + verbing" will behave as "comma+ verbing" modifier thereby giving incorrect meaning

aditya8062 wrote:however, i want to know something about option D. is option D wrong just because "simultaneously while" is redundant?
i want to know whether following (modified D) would be correct: space shuttle astronauts retrieved an orbiting satellite, while avoiding
OR will be wrong because "comma+ while + verbing" will behave as "comma+ verbing" modifier thereby giving incorrect meaning

while + VERBing serves to introduce a VERBLESS clause.
In a verbless clause, the subject and verb are omitted, but their presence is implied.
John ate while watching television.
Conveyed meaning:
John ate while [he was] watching television.
Here, the bracketed subject and verb are omitted, but their presence is implied.

D: Space shuttle astronauts retrieved an orbiting satellite, simultaneously while [they were] avoiding.
Here, the bracketed subject and verb are omitted, but their presence is implied.
Since simultaneously PRECEDES the while-clause, it cannot serve to modify the verb in the while-clause (were avoiding).
As a result, a reader might construe that simultaneously serves to modify the verb in the preceding clause (retrieved), as follows:
Space shuttle astronauts retrieved an orbiting satellite, simultaneously.
Since the correct usage of simultaneously requires TWO actions -- and the sentence above describes only one action -- the resulting meaning is nonsensical.

The following might be acceptable to GMAC:
Space shuttle astronauts retrieved an orbiting satellite while simultaneously avoiding.
An OA from GMAT Prep:
Industrialization and modern methods have improved the standard of living while at the same time introducing some 100,000 pollutants.
Here, while at the same time is not considered redundant.
Since while simultaneously conveys the same basic meaning, I would not cite this construction as a reason to eliminate an answer choice.

Thanks Guru for this insightful explaination

The following might be acceptable to GMAC:
Space shuttle astronauts retrieved an orbiting satellite while simultaneously avoiding.

i have a follow up question on this. does "COMMA + while + simultaneously avoiding" be correct?
in other words will the following be correct: Space shuttle astronauts retrieved an orbiting satellite, while simultaneously avoiding...

thanks

aditya8062 wrote:Thanks Guru for this insightful explaination

The following might be acceptable to GMAC:
Space shuttle astronauts retrieved an orbiting satellite while simultaneously avoiding.

i have a follow up question on this. does "COMMA + while + simultaneously avoiding" be correct?
in other words will the following be correct: Space shuttle astronauts retrieved an orbiting satellite, while simultaneously avoiding...

thanks

An OA from GMAT Prep:
They denounce big government, saying government is doing too much and has become too powerful, while at the same time supporting many government programs.
Here, the primary purpose of the comma preceding while is to set off the preceding non-essential modifier (saying government is doing too much and has become too powerful).
If we omit this non-essential modifier, there seems to be no need to precede the while + VERBing clause with a comma:
They denounce big government while at the same time supporting many government programs.
But given this OA, I would not cite COMMA + while + VERBing as a reason to eliminate an answer choice.

GMATGuruNY wrote:

aditya8062 wrote:Thanks Guru for this insightful explaination

The following might be acceptable to GMAC:
Space shuttle astronauts retrieved an orbiting satellite while simultaneously avoiding.

i have a follow up question on this. does "COMMA + while + simultaneously avoiding" be correct?
in other words will the following be correct: Space shuttle astronauts retrieved an orbiting satellite, while simultaneously avoiding...

thanks

An OA from GMAT Prep:
They denounce big government, saying government is doing too much and has become too powerful, while at the same time supporting many government programs.
Here, the primary purpose of the comma preceding while is to set off the preceding non-essential modifier (saying government is doing too much and has become too powerful).
If we omit this non-essential modifier, there seems to be no need to precede the while + VERBing clause with a comma:
They denounce big government while at the same time supporting many government programs.
But given this OA, I would not cite COMMA + while + VERBing as a reason to eliminate an answer choice.

Hi Mitch,

I read your post on "VERBLESS CLAUSE" modifier in which you suggested that "The implied subject of COMMA + VERBLESS CLAUSE is generally the preceding noun or noun phrase". Given your comment above, is COMMA WHILE + VERB-ING an exception to this rule? Or should I use the "VERBLESS CLAUSE" modifier rule only as last resort guessing tactic?

Many thanks in advance for any clarification you can share.