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While they remove carbon dioxide from the air, conserve soil

Expert replies
by BTGmoderatorDC » Mon Mar 05, 2018 2:10 pm
While they remove carbon dioxide from the air, conserve soil and water, and house thousands of species, forests also supply potentially valuable pharmaceuticals, and, as sources of building material and firewood, that provide employment for millions worldwide.

A. pharmaceuticals, and, as sources of building material and firewood, that provide
B. pharmaceuticals, and sources of building material and firewood, are providers of
C. pharmaceuticals and, as sources of building material and firewood that are provide
D. pharmaceuticals and as sources of building material and firewood, for providing
E. pharmaceuticals and, as sources of building material and firewood, provide

What is wrong with other options?

OA E
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Source: — Sentence Correction |

by deloitte247 » Sat Mar 10, 2018 5:50 pm
The correct answer is option Ebecause it makes grammatical and logical sense.

Option B is wrong because the auxiliary verb "are" does not act directly on the subject of the overall sentences which is the noun "forests"
Option A is wrong because taking the second part in isolation, we would have have "...potentially valuable as...sources of building material..." which gives a lexically discontinuity in the logic of the sentence.
Option D is wrong because the phrase "for providing" does not agree with the conjunction "as" that starts that clause
Option C is wrong because the concluding phrase "...and firewood that are provide" makes no grammatical sense
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by ErikaPrepScholar » Mon Mar 12, 2018 12:42 pm
We can also think about this problem as a parallelism problem. Answer choice E gives us

While they remove carbon dioxide from the air, conserve soil and water, and house thousands of species, forests also
- supply potentially valuable pharmaceuticals
and
- [as sources of building material and firewood] provide employment for millions worldwide.

Modifier "as sources of building material and firewood" is appropriately set off with commas, so we know it shouldn't affect the grammar of our sentence, and "supply" is parallel with "provide". None of the other answers have correct parallelism, so we can pick E.
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