A study of 30 years of weather pattern records of several industrializ

Question

A study of 30 years of weather pattern records of several industrialized urban areas found that weekend days tend to be cloudier than weekdays. Thus it can no longer be denied that human activity has appreciable, large-scale effects on weather, because the few seven-day cycles that occur naturally are of too little significance to cause measurable weather patterns.

Which one of the following is an assumption on which the argument depends?

(A) Industrial activity tends to decrease significantly on weekend days in the large urban areas studied.

(B) There are no naturally occurring seven-day cycles in the areas studied.

(C) If living organisms have an appreciable large-scale effect on weather patterns, then this is due at least partly to the effects of human activity.

(D) If something appreciably affects large-scale weather patterns, it is probably cyclical in nature.

(E) If a weather pattern with a natural cause has a seven-day cycle, then that cause has a seven-day cycle.

chetan2u · Accepted Answer

The para talks of a phenomenon that has been observed over last 30 years in industralized urban areas. This pattern that has been oberved has seven day cycles, where weekend days are more cloudier. So, five days of normal clouds followed by two cloudier days, and it carries on week to week.

The para then all of a sudden concludes that it is due to the human activity(industries etc) since there are no naturally occuring seven days cycle that can contribute meaningfully to this phenomenon.

Based on the above para, we have to talk of an assumption. The assumption has to be related to the   colored  bold portion  above, because the para above that is just a statement or a fact.

(A) Industrial activity tends to decrease significantly on weekend days in the large urban areas studied.
 Are we told that cloudy weather is due to industries being shut on those days? No.

(B) There are no naturally occurring seven-day cycles in the areas studied.
 The para suggest otherwise as there are few of such cycles.

(C) If living organisms have an appreciable large-scale effect on weather patterns, then this is due at least partly to the effects of human activity.
 Out of context

(D) If something appreciably affects large-scale weather patterns, it is probably cyclical in nature.
 Too extreme, as the para nowhere suggests that all changes are due to some cyclical cause.

(E) If a weather pattern with a natural cause has a seven-day cycle, then that cause has a seven-day cycle.
 Now, this option touches upon the  colored  bold portion. The para looks at only seven-day cycles that occur naturally. There could be other reasons that occur over a longer period or smaller period. It could be a mix of global warming and increase in humidity and something else that leads to low air pressure, and the conditions on weekend days are suitable for creation of clouds.
It actually could be any reason, which is out of scope here, but the most important point is that the para limits it analysis of natural reasons to those having seven day cycles.

E may be something that may not give an answer directly to what those natural reasons are, if any, but it is the best we can pick up as an assumption that the argument relies on.

akshitab2912

Nikhil55 · Answer

I am curious as to why is it not A. I had initially answered A and then looked through options again only to realize E is the right answer however, I still belive A could be the right answer too.

Palpable · Answer

Option A clearly confuses correlation with causation. We are not told if a decrease in industrial activity would lead to the weather being less cloudy or more cloudy.

Option E on the other hand, breaks the conclusion of the argument if it wasnt true. Thats your litmus test

Hope this helps.

Posted from my mobile device

WINIFREDWU1103 · Answer

Why do we care about “natural cause” not “human cause”?

aku_sunset_ · Answer

Can someone explain why E is the answer and not B?

thr3at · Answer

Can someone explain Why E is the answer, and what is the Elimination strategy for C

thr3at · Answer

Can someone explain Why E is the answer, and what is the Elimination strategy for C

VarshaGPT · Answer

Indubitably, it took me “some” time(3:00 minutes)to deduce the right answer but here is my chain of thoughts:

Almost all the answers except C looked tempting to me, however when I read E it struck me to be a more likely choice so I negated the sentence, 
“ If a weather pattern with a natural cause doesn’t have a seven-day cycle, then that cause doesn’t have a seven-day cycle.”
The argument pristinely hinges on this.

Posted from my mobile device

Nidhibatra · Answer

Can someone explain this question please

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Abulikabuli · Answer

I will try to explain as no one is addressing the issue...
A is not an assumption...
See, first identify the conclusion....Human activity is the cause.... because....
The reasoning used to justify this conclusion is the last part of the passage.
So, we will look for an option which challenges the reasoning used to come to the conclusion.
We are left with D and E, 
E kind of, I feel means to say that the cause behind 7 day cycles do not need to have a 7 day effect.
What if that cause persists even after 7 days and effects the weekend patterns?

This breaks the argument. So E. (i am not fully confident whether i am right about E, but i have to move on)

Raman109 · Answer

Understanding the argument - 
A study of 30 years of weather pattern records of several industrialized urban areas found that weekend days tend to be cloudier than weekdays. - Observation.

Thus it can no longer be denied that human activity has appreciable, large-scale effects on weather, because the few seven-day cycles that occur naturally are of too little significance to cause measurable weather patterns. - Conclusion and supporting premise.

Which one of the following is an assumption on which the argument depends?

(A) Industrial activity tends to decrease significantly on weekend days in the large urban areas studied. - The conclusion is about "human activity" and not just "industrial activity." So while industrial activity may be down, other human activity, which causes heavy traffic, or outdoor activities, which causes pollution, may still bridge the gap, and overall, the effect of human activity may stay the same.

(B) There are no naturally occurring seven-day cycles in the areas studied. - Out of scope.

(C) If living organisms have an appreciable large-scale effect on weather patterns, then this is due at least partly to the effects of human activity. - out of scope.

(D) If something appreciably affects large-scale weather patterns, it is probably cyclical in nature. - out of scope.

(E) If a weather pattern with a natural cause has a seven-day cycle, then that cause has a seven-day cycle. - what if that cause, instead of 7 days, has a biweekly cycle, and there is another natural cause that causes 4 weekly cycles, another natural cause that is also biweekly or 3 days, and all these natural factors act in unison to create a weekly impact? Then we can't say that nature is not responsible. ok.

akshitab2912 · Answer

chetan2u  : sir, can you pls explain the question premise, conclusion and stem itself - not able to make any sense out of it let alone get correct answer.

akshitab2912 · Answer

gmatophobia  hello, can you pls explain the question premise & solution?

Gemmie · Answer

The argument states that the naturally occurring seven-day cycles are insignificant in causing measurable weather patterns. It then concludes that the observed weekend cloudiness must be due to human activity.However, the argument makes an assumption about these natural cycles:

(E) If a weather pattern with a natural cause has a seven-day cycle, then that cause has a seven-day cycle.

This assumption is important because:

1. The argument dismisses natural cycles based on their period (seven days).
2. But, it's possible a natural cause with a different cycle (not seven days) could still influence weekend cloudiness.

For example, imagine the moon has a 14-day cycle that affects cloud cover. Even though the cycle isn't seven days, it could still influence weekend cloudiness depending on its alignment with the weekend.

By assuming that the cause of a natural seven-day cycle must also have a seven-day cycle, the argument weakens its case. It eliminates the possibility of other natural causes with different cycles that might explain the weekend cloud cover.

Ashutosh999541 · Answer

The change in human activity across the week is responsible for the change in cloudiness.

That’s why  Option A  is still the best available assumption—it provides the  necessary correlation  between human behavior and the observed weather pattern.

Ashutosh999541 · Answer

The change in human activity across the week is responsible for the change in cloudiness.

That???s why Option A is still the best available assumption???it provides the necessary correlation between human behavior and the observed weather pattern.

bb · Answer

Ashutosh999541 , The answer is E. Not A.
A) is a weak assumption and not the answer for a few reasons but the biggest one is that we are not told what the 7 day cycle is and if there are weekends or how that pattern works, so the argument does not depend on it being a weekend or that the cycle is even caused by an industrial activity (it may be non-industrial - we are not told). There are way too many holes in A to be the answer.

P.S. E) took me a while to wrap my mind around. I have originally discarded it as a meaningless option as I did not understand it.

A study of 30 years of weather pattern records of several industrializ

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A study of 30 years of weather pattern records of several industrializ

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