Impact craters caused by meteorites smashing into earth, have been fou

Why anwers is D ?
If I negate the conclusion breaks , i.e. The Earth's geologically stable regions have not studied more intensively by geologists than have its less stable regions.

Also D speaks about "impacts have been scattered fairly evenly over the Earth's surface "
but here we are talking about geologically stable areas and not earth's surface in general .

any expert kindly throw light on this.

D for me too ...the conclusion says the caters are due to lower rates of destructive processes. ... By dD you understand that the earth was evenly strcuk but the difference of destructive processes account for the observed difference

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Can sum1 plz explain why option B is wrong?

Try to negate option (D) -

Actual meteorite impacts have not been scattered fairly evenly over the Earth's surface in the course of Earth's geological history.
= Actual meteorite impacts have been concentrated only at a particular region through history.

This contradicts the highlighted statement in the stimulus, hence, (D) is the correct answer....

d it is ..
Impact craters have found in greatest density in geologically stable regions.
Why so :
the lower rates of destructive geophysical processes in those regions.

if we assume that meteorite struck mostly in geologically stable region , it will shatter the conclusion that geographical process is reason for wiping out the traces of craters in geographically unstable regions, and it is the frequency of meteorite showers that is causing abundant craters in geographically stable region.....

We have to assume D......

Impact craters caused by meteorites smashing into earth, have been found all around the globe but they have been found in the greatest density in geologically stable regions. This relatively greater abundance of securely identified craters in geologically stable regions must be explained by the lower rates of destructive geophysical processes in those regions.

Premise: Impact craters caused by meteorites have been found in the greatest density in geologically stable regions.
Conclusion: This occurrence is due to lower rates of destructive geophysical processes in those regions.
We have been asked to identify the gap or assumption linking these two. The argument states that the greater number of craters in geologically stable regions is due to low rates of destructive geophysical processes and not because of some other reason. We probably must eliminate the possibility of any other reason.

D states that the Actual meteorite impacts have been scattered fairly evenly over the Earth's surface in the course of Earth's geological history. - If the impacts have been scattered fairly evenly over the Earth's surface, the large numbers of craters in these regions is not because of high meteorite impacts, thus this is eliminating any alternative reasons and attributing the reason to low rates of destructive geophysical processes. Negate: "Actual meteorite impacts have not been scattered fairly evenly over the Earth's surface in the course of Earth's geological history". This breaks the argument and hence, is the correct answer.

Impact craters caused by meteorites smashing into earth, have been found all around the globe but they have been found in the greatest density in geologically stable regions. This relatively greater abundance of securely identified craters in geologically stable regions must be explained by the lower rates of destructive geophysical processes in those regions.

The conclusion is properly drawn if which one of the following is assumed?

(A) A meteorite that strikes exactly the same spot as an earlier meteorite will obliterate all traces of the earlier impact. -out of scope

(B) Rates of destructive geophysical processes within any given region vary markedly throughout geological time. -out of scope

(C) The rate at which the Earth is struck by meteorites has greatly increased in geologically recent times. -out of scope

(D) Actual meteorite impacts have been scattered fairly evenly over the Earth's surface in the course of Earth's geological history. -Correct

(E) The Earth's geologically stable regions have been studied more intensively by geologists than have its less stable regions. -Weakens the argument

Thanks.
After narrowing to choices B and D, I ended up choosing 'B'. And this explanation helps in understanding not only why 'D' is correct but also in understanding why 'B' is wrong.

If rate of geological activity varies with region, then there is no pint in mentioning geologically stable regions...
i.e. how can one say
abundance of securely identified craters in geologically stable regions must be explained by the lower rates of destructive geophysical processes in those regions.

B is clearly out

Thanks.

This one was a relatively easy one just had to figure out the reason of geological concentration if the meteroites were evenly distributed then it could be that regioins with higher stability would not have scattered the meteroite material because of which lesser stable regioins had lesser concentration therefore IMO D

One assumption in this argument would be that there is no other reason(other than being geologically stable regions) which could have caused higher rates of meteorite impacts in those regions and option D strikes at the heart of that assumption.

Impact craters caused by meteorites smashing into earth, have been found all around the globe but they have been found in the greatest density in geologically stable regions. This relatively greater abundance of securely identified craters in geologically stable regions must be explained by the lower rates of destructive geophysical processes in those regions.

The conclusion is properly drawn if which one of the following is assumed?

(A) A meteorite that strikes exactly the same spot as an earlier meteorite will obliterate all traces of the earlier impact. - WRONG. Tells nothing about rates of strike.

(B) Rates of destructive geophysical processes within any given region vary markedly throughout geological time. - WRONG. It helps the passage on one side and does not help on the other depending on the rate.

(C) The rate at which the Earth is struck by meteorites has greatly increased in geologically recent times. - WRONG. Irrelevant. Neither impacts the abundance of crater nor rates of destructive geophysical process.

(D) Actual meteorite impacts have been scattered fairly evenly over the Earth's surface in the course of Earth's geological history. - CORRECT. POE helps. So those regions where craters have not been identified may have been too geologically active.

(E) The Earth's geologically stable regions have been studied more intensively by geologists than have its less stable regions. - WRONG. May be the reason for being able to identify craters in greatest density in geologically stable regions but not that that explains lower rates of destructive geophysical processes.

Answer D.