The airline company, following through on recent warnings

[BTGmoderatorDC]

The airline company, following through on recent warnings that it might start reducing service, announced that it was eliminating jet service to nine cities, closing some unneeded operations, and it grounded twenty-two planes.

(A) closing some unneeded operations, and it grounded
(B) closing some unneeded operations, and grounding
(C) was closing some unneeded operations, while it grounded
(D) it closed some unneeded operations and grounded
(E) it was closing some unneeded operations, and grounding

OA B

Source: GMAT Prep

[ceilidh.erickson]

This question is testing PARALLELISM in a list.

If we simplify the sentence, it would read:

The airline company... announced that it was
1. eliminating jet service to nine cities
2. closing some unneeded operations, and
3. it grounded twenty-two planes.

This is clearly not a parallel list. We either need to fix the 3rd list item to match the other 2, or change the structure of the sentence overall.

(A) closing some unneeded operations, and it grounded
- not parallel

(B) closing some unneeded operations, and grounding
- eliminating, closing, and grounding is parallel. Correct!

(C) was closing some unneeded operations, while it grounded
- was eliminating, was closing, while it grounded...
- we're missing an "and" to complete the list

(D) it closed some unneeded operations and grounded
- it was eliminating, it closed, and grounded --> not parallel

(E) it was closing some unneeded operations, and grounding
- it was eliminating, it was closing, and grounding --> not parallel

The only parallel answer is B.