Geophysicist: Although scientists do not entirely agree on the causes

Question

Geophysicist: Although scientists do not entirely agree on the causes of geomagnetic reversal, they do agree that the process has the potential for significant changes on the earth. A geomagnetic reversal occurs when the magnetic field of the earth adjusts in its orientation, so that the magnetic north becomes the magnetic south, and vice versa. What is more, studies indicate that the magnetic field is gradually losing its strength and that we might expect to see a reversal within the next few millennia. While this might not seem significant, the reversal of the magnetic fields would occur over a long period of time, leaving the earth potentially unprotected from the sun’s radiation.

Reviewing the information in the passage above carefully, which of the following represents the geophysicist’s primary argument?

(A) While there will be a few effects of a geomagnetic reversal, the negative effects will be limited.

(B) Geomagnetic reversals have occurred within the period of human existence on the earth, and since mankind has survived, there is no reason to fear human eradication from geomagnetic reversal.

(C) Scientists do not fully understand the causes or results of geomagnetic reversal, but there is evidence that the process should not be ignored.

(D) Given the severe possibilities that may arise from a geomagnetic reversal, governments should begin funding studies of this process.

(E) The current placement of magnetic poles on the earth has little effect on the natural functions of the earth.

winterschool · Answer

Geophysicist: Although scientists do not entirely agree on the causes of geomagnetic reversal, they do agree that the process has the potential for significant changes on the earth. A geomagnetic reversal occurs when the magnetic field of the earth adjusts in its orientation, so that the magnetic north becomes the magnetic south, and vice versa. What is more, studies indicate that the magnetic field is gradually losing its strength and that we might expect to see a reversal within the next few millennia. While this might not seem significant, the reversal of the magnetic fields would occur over a long period of time, leaving the earth potentially unprotected from the sun’s radiation.

Reviewing the information in the passage above carefully, which of the following represents the geophysicist’s primary argument?

(A) While there will be a few effects of a geomagnetic reversal, the negative effects will be limited.  Incorrect

dont know about all effects from argument, only know about sun’s radiation

(B) Geomagnetic reversals have occurred within the period of human existence on the earth, and since mankind has survived, there is no reason to fear human eradication from geomagnetic reversal.  Incorrect

not related with argument

(C)  Scientists do not fully understand the causes or results of geomagnetic reversal, but there is evidence that the process should not be ignored.   Correct

studies about geomagnetic reversal can be an evidence, so this choice can be correct
 
(D) Given the severe possibilities that may arise from a geomagnetic reversal, governments should begin funding studies of this process.  Incorrect

argument is not express anything about governments funding 
 
(E) The current placement of magnetic poles on the earth has little effect on the natural functions of the earth.  Incorrect

additional info

Bunuel · Answer

OFFICIAL EXPLANATION

Overview:

In this question, the student is provided with a statement made by a geophysicist about geomagnetic reversal, in which the magnetic fields of the earth literally switch—with the North Pole in the south, and the South Pole pointing in the north. The geophysicist notes that many of his colleagues are still unsure of the cause of this, and not much is known, but the geophysicist goes on to stress that if such a reversal occurred, it could have the potential for causing serious problems on the earth.

According to the geophysicist, a geomagnetic reversal would occur over very long periods of time and could leave the earth exposed to radiation from the sun. The question then asks for an answer choice that represents the geophysicist’s primary argument. This is essentially a “main point” question, with the speaker of the passage identified to be a geophysicist. The student needs to peruse the passage carefully and define the main point that the geophysicist seems to be making.

There are several important features: (1) scientists do not agree on what causes geomagnetic reversal, (2) scientists do agree that there are potentially important effects, (3) geomagnetic reversal would occur gradually and not quickly, and (4) this process has the potential for leaving the earth exposed to the sun’s radiation. These four ideas indicate the primary foci of the paragraph, so the correct answer choice will combine them into a single coherent statement.

The Correct Answer:

C Answer choice (C) best combines the four ideas noted in the Overview above into a unified thought: scientists do not necessarily know the causes or even the results of geomagnetic reversal, but there is enough evidence to indicate that they should be paying close attention to it. Answer choice (C), therefore, is correct.

The Incorrect Answers:

A There is nothing in the passage to indicate that the geophysicist believes the information in answer choice (A). In fact, the geophysicist seems to believe that geomagnetic reversal could be a very serious issue with significant and dangerous effects. Answer choice (A) cannot be correct.

B The geophysicist makes no mention of previous geomagnetic reversals, and while the potential does exist for them to have occurred in the past, there is definitely not enough information in the passage to suggest that such a process did occur before or that it occurred while mankind lived on the earth. Answer choice (B) attempts to infer details that the passage does not provide, so it is incorrect.

D The geophysicist clearly believes that scientists should be paying attention to the potential for geomagnetic reversal, but there is no mention of government funding, nor does the geophysicist discuss anyone outside the scientific community. Answer choice (D) cannot be correct.

E The geophysicist does not clearly discuss the effects that the magnetic poles currently have on the natural functions of the earth, but given the concern that is expressed over geomagnetic reversal, it stands to reason that the geophysicist does not agree with answer choice (E). Therefore, answer choice (E) cannot be the geophysicist’s main point, so it may be eliminated.

Ishaan30 · Answer

Scientists do not fully understand the causes or  results  of geomagnetic reversal, but there is evidence that the process should not be ignored.
Passage -

The passage doesn't say that scientists do not understand the effects of geomagnetic reversal. No other answer makes sense but C had a big red flag because of this one word. Can someone explain why C is still the answer?

Geophysicist: Although scientists do not entirely agree on the causes

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Geophysicist: Although scientists do not entirely agree on the causes

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