The blue-eared slider dwells only in slow-moving streams

Question

Blue-eared sliders dwell only in slow-moving brooks where organic debris settles and accumulates. In almost all places in Guwahati where blue-eared sliders used to thrive, suburban development has cleared uplands and put down asphalt. As a result, rainwater now runs directly into brooks, resulting in an increased flow that slows the amassment of organic sediments. Hence, it is probably the increased flow caused by suburban development that is responsible for the blue-eared sliders' virtual disappearance from Guwahati.

Which of the following, if true, most strongly supports the argument?

A. The green-eared slider, a species that lives in both slow and swift moving waters, continues to thrive in streams in Guwahati from which blue-eared sliders have disappeared.

B. Since 1980 the suburban population of Guwahati has grown ten times faster than urban population.

C. Blue-eared sliders have disappeared in the past ten years from some suburban areas of another city, Leh, that were originally developed more than a century ago and that have not experienced significant development for decades.

D. Suburban development in Guwahati contributes significantly to pollution of local streams with lawn fertilizers that are poisonous to most small aquatic animals.

E. Much of the suburban development in Guwahati has been occurring in areas that never provided prime habitat for blue-eared sliders.

sherlocked221B · Answer

Is A not irrelevant here? When we are not talking about other green-eared slider?

bronaugust · Answer

To solve this question, let us deploy    IMS's four-step technique   .

STEP #1  ->   IDENTIFY THE QUESTION TYPE

To identify the question type, we must read the question stem. The question stem states, 'Which of the following, if true, most strongly supports the argument?' Clearly, what we have is a strengthening question.

Now that the question type is identified, let us proceed to the second step.

STEP #2  ->    DECONSTRUCT THE ARGUMENT

In a strengthening question, it is a must to deconstruct the argument by figuring out the premise and conclusion. Let us now read and deconstruct the argument.

CONCLUSION:   It is probably the increased flow caused by suburban development that is responsible for the blue-eared sliders' virtual disappearance from Guwahati.

PREMISE:   In almost all places in Guwahati where blue-eared sliders used to thrive, suburban development has cleared uplands and put down asphalt. As a result, rainwater now runs directly into brooks, resulting in an increased flow that slows the amassment of organic sediments.

Now that the argument is deconstructed, let us proceed to the third step.

STEP #3  ->   FRAME A SHADOW ANSWER

Remember we are looking to strengthen the argument, and a great way of strengthening the argument is by introducing an extra premise that justifies the conclusion. The author concludes his argument by stating that it is probably the increased flow (of waters in brooks) caused by suburban development that is responsible for the blue-eared sliders' virtual disappearance from Guwahati. In this argument, the pattern is evidently causal. In other words, the author says the virtual disappearance of the blue-eared slider from Guwahati is caused by the increased flow of water in the brooks in which they thrived before. We already know from the argument that blue-eared sliders dwell only in slow-moving brooks. Let us now frame a shadow answer.

SHADOW ANSWER:   Any situation that justifies the author's argument that it is the increased flow of water in the brooks that resulted in the virtual disappearance of blue-eared sliders.

Now that we have come up with a shadow answer, let us proceed to the final step.

STEP #4  ->   PROCESS OF ELIMINATION

A. The green-eared slider, a species that lives in both slow and swift moving waters, continues to thrive in streams in Guwahati from which blue-eared sliders have disappeared. -   MATCHES THE SHADOW ANSWER   -  If the green-eared slider lives in both slow and swift moving waters, and if it continues to thrive in streams from which blue-eared sliders have disappeared, it validates the author's conclusion that the increased flow of water in brooks caused the virtual disappearance of the blue-eared slider. Remember, we already know that blue-eared sliders live only in slow-moving waters, but if green-eared sliders actually continue to thrive in the very same waters, the author's conclusion is justified.  -   KEEP

B. Since 1980 the suburban population of Guwahati has grown ten times faster than urban population. -   NOT A MATCH   -  Not worried about the stated comparison between suburban and urban population.  -   ELIMINATE

C. Blue-eared sliders have disappeared in the past ten years from some suburban areas of another city, Leh, that were originally developed more than a century ago and that have not experienced significant development for decades. -   NOT A MATCH   -  It does not tell us whether it is the increased flow of water that led to the disappearance of blue-eared sliders.  -   ELIMINATE

D. Suburban development in Guwahati contributes significantly to pollution of local streams with lawn fertilizers that are poisonous to most small aquatic animals. -   NOT A MATCH   -   Again, does not tell us whether it is the increased flow of water that led to the disappearance of the blue-eared slider.  -   ELIMINATE

E. Much of the suburban development in Guwahati has been occurring in areas that never provided prime habitat for blue-eared sliders. -   NOT A MATCH   -  The answer we are looking for should strengthen the causal link between the increased flow of waters in brooks and disappearance of blue-eared sliders. This answer option, which speaks of suburban development occurring in areas that never provided prime habitat for blue-eared sliders, does not do that.  -   ELIMINATE  
 
  Hence, A is the correct answer.

bronaugust · Answer

Hi, jaswanth_ss!

We are looking to strengthen the author's conclusion that says it is the increased flow of waters in the brooks that has caused the virtual disappearance of blue-eared sliders in Guwahati. Now, let us analyse answer option (A). If the green-eared slider lives in both slow and swift moving waters, and if it continues to thrive in streams from which blue-eared sliders have disappeared, it validates the author's conclusion that the increased flow of waters in brooks caused the virtual disappearance of the blue-eared slider. Remember, we already know that blue-eared sliders live only in slow-moving waters, but if green-eared sliders actually continue to thrive in the very same waters, the author's conclusion is justified.

The blue-eared slider dwells only in slow-moving streams

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The blue-eared slider dwells only in slow-moving streams