My advice is two-fold:
1. With every CR passage, you should identify the conclusion first. If you don't ID the conclusion, you'll have a hard time determining the role of the bold portions. This is because the bold portions typically relate to the conclusion somehow. For example, they might be supporting premises, contradictory premises, or even the conclusion itself.
2. "Split" the answers just as you would with Sentence Correction. If you decide the first bold section is a premise supporting the conclusion, look through the five answer choices and cross off all the answers which describe the first bold section as anything else. This is a good time-saving technique that allows you to leverage a single decision to knock out a few answer choices.
All that said, these questions are very rare. I'd need more information, but I might advise you to focus your time elsewhere even if this is your greatest weakness.
Brett Beach-Kimball | Manhattan GMAT Instructor
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