Members of the Amazonian Akabe people commonly take an early-morning

[quote="Utk147"]Why can't it be option E as it also weaken the argument?
Is there any specific rule to abide by.


E actually strengthens the argument.

Anthropologists hypothesize that since this
tea is extraordinarily high in caffeine, the explanation
for the Akabe’s not drinking more of it at dawn is
that high caffeine intake would destroy the
surefootedness that their daily tasks require.

Anthropologists argue because of the high caffeine content, the Akabe take the tea in small amounts so as not to interfere with their daily tasks. and E. When celebrating the condition of performing daily tasks would seemingly go away and so allow them to take it in large amounts. option C undermines their explanation by providing an alternative explanation for the reason why they take the tea in small amounts (before performing daily tasks).

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Causal reasoning

Cause: tea is extraordinarily high in caffeine
Effect: Akabe only drink a little of their tea in the morning

We have to weaken the argument with causation flaw. So, we have to do one of the following: (1) show that there is no cause and effect relationship; (2) show that cause and effect relationship is reversed; (3) find an alternate cause.
(C) provides alternate cause or another possible reason why the people don't drink a lot of tea in the morning - it contains a narcotic.

(E) is incorrect because it is irrelevant. Argument is about why they don't drink much in the morning

B is a great trick answer, as i found myself bringing in indirectly caffeine/evening and choosing it without thinking the main issue in argument is 'days tasks'

Use the elimination strategy - only C makes somehow some sense.

Members of the Amazonian Akabe people commonly take an early-morning drink of a tea made from the leaves of a forest plant. Although they greatly enjoy this drink, at dawn they drink it only in small amounts. Anthropologists hypothesize that since this tea is extraordinarily high in caffeine, the explanation for the Akabe’s not drinking more of it at dawn is that high caffeine intake would destroy the surefootedness that their daily tasks require

Fact: not drinking more of a kind of tea
Explanation: drink more --> more caffeine --> destroy surefootedness

Which one of the following, if true, most seriously calls the anthropologists’ explanation into question?

To attack this explanation, we must have other way to explain the connection: drink more ---> ??? ---> destroy surefootedness


(A) The drink is full of nutrients otherwise absent from the Akabe diet. irrelevant. We don't care about nutrients

(B) The Akabe also drink the tea in the evening, after their day’s work is done. If they drink tea in the evening --> caffeine in the evening --> don't care about caffeine effect in the evening. But it has nothing to do with the effect of caffeine with the surefootedness during the workday.

(C) The leaves used for the tea contain a soluble narcotic. So the tea has narcotic, which makes users dizzy. This is an explanation why drinking more tea means losing surefootedness --> CORRECT

(D) Akabe children are introduced to the tea in only a very weak form. We don't care about children

(E) When celebrating, the Akabe drink the tea in large quantities. We don't care what the Akabe do during party time.

The conclusion is: Members of the tribe drink the tea in small quantities because the tea contains high levels of caffeine.

(A) The drink is full of nutrients otherwise absent from the Akabe diet.
- This doesn't impact the conclusion. Sure, the tea is full of nutrients but how does that explain the small amounts in which the members take the tea. If let's say that the only way the nutrients in tea are effective is when the tea is sipped in small amounts, then perhaps this answer would have been worth considering.

(B) The Akabe also drink the tea in the evening, after their day’s work is done.
- This strengthens the argument. The anthropologists believe that the reduced intake is to make sure that the members are able to do their daily work. If they are drinking the tea after the day's work is done then it means that the high caffeine does interfere with their work.

(C) The leaves used for the tea contain a soluble narcotic.
- C is the answer because C presents an alternative reason to the anthropologist's hypothesis. It is not the caffeine but the narcotic that is the reason for drinking the tea in small amounts. The argument is about the reason why the members of the tribe drink the tea in small amounts. The anthropologists believe it is the high caffeine content but we can the weaken that argument by saying - no, it is not, it is actually the presence of a narcotic element in the tea which is why the tea is sipped in small amounts.

(D) Akabe children are introduced to the tea in only a very weak form.
- This is irrelevant.

(E) When celebrating, the Akabe drink the tea in large quantities
- Again, irrelevant. How does the impact the conclusion?

Can't D mean:
Akabe children are introduced tea and it become as habit of theirs since childhood to take in weak form . Thus now adults take in small quantity, not because of high caffenine intake limitations. Thus it can't weaken the argument?

In my opinion, I eliminated it because I thought it was strengthening the argument. If we believe that the high caffeine interferes with the performance of daily routine work then children should be given the tea in a weaker form (dissolving the high caffeine), presumably the high caffeine would not be healthy for kids. Also, option D talks about the strength of caffeine in the tea; the argument is about the reason why adults drink the tea in small quantities.

Hope this helps.

A helpful tip to weaken a purported causation relationship is to find another Z to purported causation X => Y. Here only C provides the alternative reason Z that we are supposed to look for.

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