Critical Reasoning

This is from the Princeton Review, Bin 3 of the practice verbal section. I have been evaluating the explanation at the back for the last like 10 minutes. I couldn't seem to wrap myself on the concept until just recently. Wanted to share this and see if you guys shared the same thoughts. I answered D. The books answer is below. Let's start with the question:

Scientists today accept that the increased severity of hurricanes in the last 10 years has been a result of warmer water in the Caribbean, which "feeds" the storms as they pass over it by a mechanism not yet completely understood. Thus, these severe hurricanes are yet more evidence of global warming.

Which of the following, if true, would most strengthen the argument above?

A. Accurate statistics on the warming of the earth do not go back more than 100 years.
B. Scientists have not discovered a new undersea current, fueled by an undersea volcano, which could have funneled warmed water into the Caribbean.
C. The arctic ice caps have been losing three feet of circumference each year for the past five years.
D. A new modeling computer program projects that the severity of hurricanes will increase over the next 10 years.
E. Some scientists believe they will soon prove that the mechanism by which a storm picks up energy from warm water is based on convection.


Here is the explanation from the book:

The best answer is B. While choice B might seem unlikely, it strengthens this casual argument by removing a possible alternate cause. Took me a while to wrap myself around this, because it seemed to be 99% times that if B were true, i would bring up an alternative cause which theoretically should "weaken" the relationship. After re-reading it for 20 minutes, I guess what the explanation is saying is that if it were TRUE that scientists have NOT found the undersea volcano yet, then that is more reason why they arrived at the original argument in the paragraph.

The only way I could grasp my mind to accept that explanation is by thinking mathematically, and that still took me a long time AFTER reading the explanation. Does anyone else agree with me here?

Does this mean for strengthen questions on casual relationships, I should try to find the one that eliminates an alternative cause?

Much appreciated in advance.

Think a bit more about the focus of the passage as opposed to dissecting pieces of the argument

A) Off scope, we are talking about events in the past ten years and their affect on temps
B) Correct, confirms that the cause of the increased severity is not fully understood.
C) Off scope again, we are talking about warm water in the Caribbean not the ice caps.
D) Not worried about the future
E) We are not concerned with other theories

Jim@StratusPrep wrote:Think a bit more about the focus of the passage as opposed to dissecting pieces of the argument

A) Off scope, we are talking about events in the past ten years and their affect on temps
B) Correct, confirms that the cause of the increased severity is not fully understood.
C) Off scope again, we are talking about warm water in the Caribbean not the ice caps.
D) Not worried about the future
E) We are not concerned with other theories

Thanks for taking the time to reply Jim! Here's my follow-through question.

To me, the question is asking to strengthen the original cause-effect argument that the severe hurricanes are evidence of global warming. Going by your B, how does confirming it's true that the cause of the increase severity is not fully understood a way to strengthen the original argument?
I would think that would actually weaken it, since that means there are other causes not yet known.

Nevermind, I just got it after talking it over with a friend for a good amount of time.

If B were true, that means we know for SURE (100% true) that they have not found the cause of the volcano. So there is no way that is a cause, because it has not been found by Scientists yet. It can never be a cause. It's like before Eve ate the apple, then her knowing she is naked would never be a possibility. Because Scientists never found about the volcano, then that can never be a cause of increased hurricanes. Therefore, a better of a chance that global warming really is the cause.

Scientists today accept that the increased severity of hurricanes in the last 10 years has been a result of warmer water in the Caribbean, which "feeds" the storms as they pass over it by a mechanism not yet completely understood. Thus, these severe hurricanes are yet more evidence of global warming.

Which of the following, if true, would most strengthen the argument above?

A. Accurate statistics on the warming of the earth do not go back more than 100 years.
B. Scientists have not discovered a new undersea current, fueled by an undersea volcano, which could have funneled warmed water into the Caribbean.
C. The arctic ice caps have been losing three feet of circumference each year for the past five years.
D. A new modeling computer program projects that the severity of hurricanes will increase over the next 10 years.
E. Some scientists believe they will soon prove that the mechanism by which a storm picks up energy from warm water is based on convection.




kellogs4toniee
Yes B is the right answer. I honestly do not know what the princeton book tells but i will try to give you my explanation of what I understood it and what did I apply.

This is basically a case of causal reasoning wherein X causes Y.
Inorder to prove X causes Y, either prove actually that X causes Y or also indicate that some other variables or parameters do not cause Y; eg: A,B,C, Z or any other reason does not cause Y.

Read the critical reasoning bible for understanding the causal reasoning aspect.

Also lets go down to the options and see which is the best one of them...

A] Out of scope as it does not affect the argument at all.

C] This says something about Artic Ice caps which is irrevelant. Even if we consider it a reason for global warming or a symptom of global warming, we cant prove X causes Y. This can prove to be Z causes Y which somewhere weakens the argument.

D] Out of scope. Neither strengthens or weakens the argument.

E] Again weakens the argument by saying that some other parameter causes Y, not X. Hence not acceptable



Hence left with B.

Hope
kellogs4toniee
you got the explanation......