Since 1985, pollution levels in Lake Thomas have dropped

Question

Since 1985, pollution levels in Lake Thomas have dropped considerably primarily because of a state program to clean the lake water by means of a water refinery. Ironically, during this same period, the once-abundant population of sunfish in the lake has dwindled.

Which of the following, if true, would best explain why the sunfish population of Lake Thomas has dwindled at the same time that the lake water has become cleaner?

a. The life spans of sunfish are not diminished by high pollution levels, but the number of offspring they create during their lifetime is diminished.

b. Several artificial chemicals are introduced into the lake as a result of the refinement process, but these chemicals are known to have a benign effect on fish.

c. The water refinement process creates an environment extremely favorable to pike, a predator fish.

d. The heaviest concentrations of sunfish population in the lake are at its northern and northeastern shores, many miles away from the water refinery.

e. Ever since 1972, a strictly enforced state regulation has prevented anglers from over-fishing Lake Thomas.

MA · Answer

C. The water refinement process creates an environment extremely favorable to pike, a predator fish.

Gauss · Answer

Since 1985, pollution levels in Lake Thomas have dropped considerably primarily because of a state program to clean the lake water by means of a water refinery. Ironically, during this same period, the once-abundant population of sunfish in the lake has dwindled.

Which of the following, if true, would best explain why the sunfish population of Lake Thomas has dwindled at the same time that the lake water has become cleaner?

a. The life spans of sunfish are not diminished by high pollution levels, but the number of offspring they create during their lifetime is diminished.  does not address passage
 
b. Several artificial chemicals are introduced into the lake as a result of the refinement process, but these chemicals are known to have a benign effect on fish.  then out we should explain why less fish cleaner water 

c. The water refinement process creates an environment extremely favorable to pike, a predator fish. i s the right one  

d. The heaviest concentrations of sunfish population in the lake are at its northern and northeastern shores, many miles away from the water refinery.  but this does not justify the fact that the fish are declinging there should be another reason that could explain this paradox
 
e. Ever since 1972, a strictly enforced state regulation has prevented anglers from over-fishing Lake Thomas. then the nr of fish should increase

haas_mba07 · Answer

c. The water refinement process creates an environment extremely favorable to pike, a predator fish.


A. This is cause decling even with pollution.

B. No affect on the population "benign"

C. Predator thrives sunfish population declines... correct answer.

D. Out of scope

E. Out of scope.

u2lover · Answer

no doubt here about C

we need to find alternative reason for lower population of this sunfish, that is not directly related to cleaning the pollution of the lake, which is C

ps_dahiya · Answer

I think its C.

Praetorian · Answer

Good Job.

Again, akamaibrah was gracious enough to explain:

"My choice is definitely C.

Remember, we are trying to explain the decrease in Sunfish...

(A) states that number of offspring is DIMINISHED by pollution. Hence, if we REDUCE pollution, offspring will no longer be diminished. This certainly does not explain the decrease in Sunfish -- more likely it inplies that an eventually increase will occur.

(B) states that the chemical do not harm fish. Hence, this does not explain the decrease in Sunfish.

(C) states that a predatory fish thrives in the environment created by the refinery. Nitpicking aside, since the subject of the argument is the "sunfish", it is reasonable to assume that the term "predatory" refers to the relationship of the pike to the sunfish. This would certanly explain a decrease in sunfish and IMO is the best choice.

(D). states that the heaviest concentration of pike are far away from the refinery. While this is consistent with (C), it does not in itself explain an overall decrease in the sunfish population.

(E) does nothing to explain the decrease in Sunfish since 1985 and is irrelavent. In fact, it removes a possible explaination for the decrease."

jaynayak · Answer

Clear winner C.

hemamalinidr · Answer

I will also go with C.

xsports · Answer

Could you give us the OA Praetorian.

I have a problem with C - it mentions 'creates an environment extremely favorable to pike' - this does not imply that pikes exist in the lake as well. All it says is that the environment is pike friendly.

sumitsarkar82 · Answer

C it is........

Futuristic · Answer

C it is

Since 1985, pollution levels in Lake Thomas have dropped

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