fozzzy wrote:
Can someone explain why option C and D is incorrect! Thanks
Hi fozzy.
Whereas the use of synthetic fertilizers has greatly expanded agricultural productivity in many parts of the world,
an increase in their use can create serious environmental problems such as water pollution, and their substitution for more traditional fertilizers may accelerate soil structure deterioration and soil erosion.
A. an increase in their use can create serious environmental problems such as water pollution, and their substitution for more traditional fertilizers
Correct. The use of "their" is quite ambiguous, so I don't think this sentence sounds smoothly. A, however is the best among all options.
B. an increase in their use can create serious environmental problems
like water pollution, and if substituted for more traditional fertilizers,
itWrong.- "like" is incorrect, like = similar to. However, wee need examples here, thus "such as" is appropriate.
- We're talking about "fertilizers" (plural) ==> "it" is wrong.
C. if
these fertilizers are used increasingly, they can create serious environmental problems such as water pollution, and if used as substitutions for more traditional fertilizers, they
Wrong.- Parallelism: The structure of C is: whereas
the use of X has greatly expanded........, if
X are used, and if ......
==> in order to make a sentence parallel, the structure should be: whereas the use of X greatly expanded......, in increase in their use.......
==> "the use of X" || "their use"
- Meaning: "an increase in the use of synthetic fertilizers" DIFFERS from "the fertilizers are used increasingly"
For example: (1)
The increase in the use of computers ==> computers become more popular, so many people use them.
(horizontal)(2)
The Computers are used increasingly ==> These particular computers are exploited
(vertical)D. the increased usage of these fertilizers can create serious environmental problems such as water pollution, while if substituted for more traditional fertilizers, this substitution
Wrong.- Modifier problem: "if substituted for more ..., this substitution may accelerate .........."
Verb-ed modifier + COMMA ==> ALWAYS modify subject. The subject of the second part is "this substitution" ==> The meaning will be:
if substitution are substituted for more...... ==> Does not make sense at all.
- "While" is subordinating conjunction ==> does not match the overall meaning of the structure. Coordinating conjunction "and" is more appropriate.
E. the increased usage of these fertilizers can create serious environmental problems
like water pollution,
while their substitution for more traditional fertilizers
Wrong.- "like" is wrong ==> "such as" should be correct.
- "while" changes meaning. ==> "and" should be correct
Hope it helps.