as for why (b) is correct:
Step 3: Choice (B) makes it an incomplete sentence. We need verb here to complete the sentence.
nope. this is a correct, albeit not very common, form of modifier.
i'm not 100% sure what it's called -- it might be "absolute phrase", though i don't think that's quite right -- but here's how it's used:
this sort of modifier (COMMA + ABSTRACT NOUN) can be used to refer back to the WHOLE IDEA of the preceding clause.
let's say that scientists discover that X is 60 percent of Y, and that they are shocked by this finding.
then:
recent studies have shown that X is 60 percent of Y, which has shocked many in the scientific community.
incorrect.
this sentence implies that Y itself has shocked many in the scientific community. that's not true.
recent studies have shown that X is 60 percent of Y, a finding that has shocked many in the scientific community.
or
recent studies have shown that X is 60 percent of Y, a statistic that has shocked many in the scientific community.
these are correct.
the abstract noun "finding" or "statistic" may refer to the whole idea of the preceding clause.
in fact, that's the whole point of these modifiers. they are fatally awkward in spoken language (i.e., you can NEVER EVER say them out loud), but they do things that more "normal-sounding" modifiers (such as "which") aren't allowed to do.
for 2 problems that use this sort of modifier, see:
* #59 in the purple OG verbal supplement (in which this sort of modifier is present in the NON underlined section)
* #79 in the same source (in which it's present in the correct answer choice)
Ron has been teaching various standardized tests for 20 years.
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Pueden hacerle preguntas a Ron en castellano
Potete chiedere domande a Ron in italiano
On peut poser des questions à Ron en français
Voit esittää kysymyksiä Ron:lle myös suomeksi
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Yves Saint-Laurent
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