Early in the twentieth century, Lake Konfa became very polluted. Recently fish
populations have recovered as release of industrial pollutants has declined and the lak
waters have become cleaner. Fears are now being voiced that the planned constructio
an oil pipeline across the lake’s bottom might revive pollution and cause the fish
population to decline again. However, a technology for preventing leaks is being
installed. Therefore, provided this technology is effective, those fears are groundless
The argument depends on assuming which of the following?
A. Apart from development related to the pipeline, there will be no new industria
development around the lake that will create renewed pollution in its waters.

B. Other than the possibility of a leak, there is no realistic pollution threat posed to
the lake by the pipeline’s construction.
C. There is no reason to believe that the leak-preventing technology would be
ineffective when installed in the pipeline in Lake Konfa.
D. Damage to the lake’s fish populations would be the only harm that a leak of oil
from the pipeline would cause.
E. The species of fish that are present in Lake Konfa now are the same as those that
were in the lake before it was affected by pollution.
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A- this is out of scope
C - The argument already says that provided the technology is effective.
D - Again kind of a shell game choice, kind of distracting to me.
E - Negating this choicedoes not affect the conclusion-even if they are not the same, they might still be affected by the pollution.

I think B stands out for me. If there are other sources of pollution than the oil leak, then this argument falls through.

A should be OA
B is trap!
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A and b are so close ... how can you decide ? I went with B because it seemed to be closer to the stem than A, because b specifically mentions the construction of the pipeline and leaks

Early in the twentieth century, Lake Konfa became very polluted. Recently fish
populations have recovered as release of industrial pollutants has declined and the lak
waters have become cleaner. Fears are now being voiced that the planned constructio
an oil pipeline across the lake’s bottom might revive pollution and cause the fish
population to decline again. However, a technology for preventing leaks is being
installed. Therefore, provided this technology is effective, those fears are groundless
The argument depends on assuming which of the following?
A. Apart from development related to the pipeline, there will be no new industria
development around the lake that will create renewed pollution in its waters.
B. Other than the possibility of a leak, there is no realistic pollution threat posed to
the lake by the pipeline’s construction.
C. There is no reason to believe that the leak-preventing technology would be
ineffective when installed in the pipeline in Lake Konfa.
D. Damage to the lake’s fish populations would be the only harm that a leak of oil
from the pipeline would cause.
E. The species of fish that are present in Lake Konfa now are the same as those that
were in the lake before it was affected by pollution.

****
The argument is based on the possible threats due to the pipeline construction not the about the pollution causing sources or pollution itself. It states a fact that the pollution infact declined due to declined release of pollutants from the industries. Hence, we must focus on possible threats - pollution by the leak and threat to fish population as possible out comes of damage to pipeline and assumptions made. The author addresses both the concerns in his argument -

"Fears are now being voiced that the planned construction of an oil pipeline across the lake’s bottom might revive pollution and cause the fish population to decline again. However, a technology for preventing leaks is being
installed."

On review of answers now:

A. Apart from development related to the pipeline, there will be no new industria
development around the lake that will create renewed pollution in its waters.
*** This can be eliminated as the passage states the pollution declined due to reduction in the release of pollutants as a fact.*

B. Other than the possibility of a leak, there is no realistic pollution threat posed to
the lake by the pipeline’s construction.
***This is a possible assumption of the author. *

C. There is no reason to believe that the leak-preventing technology would be
ineffective when installed in the pipeline in Lake Konfa.
***The author state "provided" that means the leak is possible despite the availability of leak proof technology*

D. Damage to the lake’s fish populations would be the only harm that a leak of oil
from the pipeline would cause.
***This is untrue, as the author says - "Fears are now being voiced that the planned constructio
an oil pipeline across the lake’s bottom might revive pollution and cause the fish
population to decline again. "

E. The species of fish that are present in Lake Konfa now are the same as those that
were in the lake before it was affected by pollution.
***There is nothing in the passage that says survival of the fish population vary with differences in their species.


Now, upon reviewing the analysis above, the best answer is B, that the author's argument included the assumption that construction of pipeline itself is not a threat.

using A - the whole thing makes sense...