While they remove carbon dioxide from the air, conserve soil

Question

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 providing

(D) pharmaceuticals and as sources of building material and firewood, for providing

(E) pharmaceuticals and, as sources of building material and firewood, provide

orsang8 · Accepted Answer

I would say E
kinda like "forest also SUPPLY x and (,modifier,) provide Y
E. pharmaceuticals and, as sources of building material and firewood, provide

Whats OA?

ChrisLele · Answer

In this sentence 'forests' do two things: A and B. Therefore we need Parallel structure. To elaborate: forests also Verb1 (supply) Phrase1, and Verb2 Phrase 2. Therefore we can home in right away at the end of the underlined part, looking for a verb that matches 'supply' in tense. The only answer that works is (E), which has 'provide.'

The other twist to this sentence is there is an interrupting phrase: '..., as sources of...firewood, ...'. An interruptor should be set off by a comma at the beginning of the phrase and one at the end of the phrase. Only (A) and (E) do so, however (A) is wrong because 'that provide' is not parallel to 'supply.'

Hope that clears things up

.

agdimple333 · Answer

87. 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 -  comma twice looks awkward, 'that' changes the meaning 
B. pharmaceuticals, and sources of building material and firewood, are providers of -  comma after pharmaceuticals is ambiguous  
C. pharmaceuticals and, as sources of building material and firewood that are provide -  that are provide?  
D. pharmaceuticals and as sources of building material and firewood, for providing -  for providing?, also you need comma after 'and' 
E. pharmaceuticals and, as sources of building material and firewood, provide -  makes most sense

metallicafan · Answer

+1 E

This sentence requires parallelism for the verbs: supply and provide (both have to be working verbs).

uledssul · Answer

87. 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

I think this particular problem is more related with the meaning of the sentence.

Forests supplies pharmaceuticals.
and 'as sources of building material and firewood' forests provide employment for millions worldwide.

The above combination conveys the meaning clearly.

A. pharmaceuticals,  and , as sources of building material and firewood, that provide 
'and' creates a fragment sentence

B. pharmaceuticals, and  sources of building material and firewood , are providers of 
meaning distortion

C. pharmaceuticals and, as sources of building material and  firewood that  are provide 
meaning distortion

D. pharmaceuticals and   as sources of building material and firewood  ,  for providing  
parallelism, 'for providing' meaning distortion

E. pharmaceuticals and, as sources of building material and firewood, provide
correct

manikanth · Answer

why there should not be "that" in E option. that provide.

where and when we should use "that " normally ?

neutronstar · Answer

Primarily there are  2 usages  of that:
1. As a Noun
2. As a connector.

1. As a Noun 
Chairs that don’t have cushions are uncomfortable to sit on. Note that, here 'that' refers back to chairs. Because Chairs is a plural noun, you should use verb - do + not for a plural noun = Don't (and not doesn't)

2. As a connector 
Eg. I believe that he is innocent.

Let me come back to the quetion:
While  they (referring to forests)  remove carbon dioxide from the air, conserve soil and water, and house thousands of species,

forests also

1. supply potentially valuable pharmaceuticals and  (note here there are only 2 items in the list and hence we use just AND. We do not use comma + and) 
2. provide employment for millions worldwide.

Now, 2nd act of providing employment has a  modifier which is introduced by way of a phrase between two commas :
, as sources of building material and firewood,

Do not mistake to refer the first comma from modifier with and preceding that comma.

Key in solving SC question is Meaning (and not the grammar)!

Cheers!

LogicGuru1 · Answer

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 --> NOT PARALLEL
B. pharmaceuticals,  and sources  of building material and firewood, are  providers of  --->NOT PARALLEL; INCORRECT MEANING
C. pharmaceuticals and, as sources of building material and firewood  that are  provide ---> NOT PARALLEL
D. pharmaceuticals and as sources of building material and firewood,  for providing  -----> NOT PARALLEL
 E. pharmaceuticals and, as sources of building material and firewood, provide ----> correct

Parallelism is at play here
Clearly the correct answer is E

svasan05 · Answer

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  "that" incorrect modifies "building material and firewood" - it is the forests that provide employment. Eliminate.

(B) pharmaceuticals, and sources of building material and firewood, are providers of  Placement of "and" implies that forests  provide  "sources of building material and firewood". Original meaning is that the forests are the sources themselves. Eliminate.

(C) pharmaceuticals and, as sources of building material and firewood that are providing  Same error as in (A). Eliminate.

(D) pharmaceuticals and as sources of building material and firewood, for providing  Let's focus on the last part of the sentence: "...forests  also supply potentially valuable pharmaceuticals and  as sources of building material and firewood,  for providing  employment for millions worldwide". Clearly an incomplete sentence fragment, not to mention the same meaning error in "source" as in (A) and (C). Eliminate.

(E) pharmaceuticals and, as sources of building material and firewood, provide  Correct answer - above errors are eliminated and no new errors are introduced.

waytowharton · Answer

KarishmaB  and other experts

I was able to eliminate other options, but i am not sure what role does "as sources of building material and firewood" play in Option E. Please do help me. Thanks in advance!

KarishmaB · Answer

The sentence tells us that forests provide employment for millions. But how can forests provide employment? Hence, the sentence clarifies 'as sources of building material and firewood.' Since forests are sources of building material (wood) and firewood, many people are employed to chop trees and transport wood out of the forests etc. Hence, they act as sources of employment.

sumit99kr · Answer

While they (forests) remove..., conserve..., and house...,forests also supply X and ,...., provide Y for millions worldwide.

Hence E is the correct choice.

Two concepts are tested here-
Paralleslism 
non-essential modifier.

Posted from my mobile device

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While they remove carbon dioxide from the air, conserve soil

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