We’ve got a Main Conclusion question which we know from the question stem: Which one of the following most accurately expresses the main conclusion of the argument?

Moving onto the stimulus:

We start out with the notion that chemical fertilizers are very bad for a couple reasons: 1) they create health issues and 2) they kill worms, which are beneficial for soil.

Then we get the word “for” which some of you may recognize as an indicator that precedes a premise but is often part of a sentence that also includes a conclusion. Interesting. Is that the case here? Let’s take a closer look.

We’re told “for this reason.” What reason? Well “this reason” is a referential phrase referring to the second effect of chemical fertilizers we were presented with in the opening sentence. If we insert the information that “this reason” is referring to and paraphrase a bit, the second sentence would read like: “Because fertilizers destroy earthworms, the use of chemical fertilizers should be avoided.” So now we can see that the opening clause of this sentence provides support for the second clause. We can apply the why test just to make sure: Why should we avoid chemical fertilizers? Well because fertilizers destroy earthworms. The only way we can work out the full meaning of this sentence though, is by unpacking the referential phrase within it. Ok so we’ve identified at least one premise and conclusion. Now let’s move on to the third sentence.

If we look closely at the third sentence we see the word “thus” which is a conclusion indicator. But I thought we already found our conclusion? Not so fast! We found one conclusion! That doesn’t mean there can’t be more! When we take a closer look, we find a conclusion in the second clause of this sentence immediately following the word thus: “a garden rich in earthworms is much more fertile than a garden without them.” Working backwards we can see support in the first clause of this sentence. Again, we can apply the why test to test this support relationship: Why is a garden rich in earthworms much more fertile than a garden without them? Well because the castings they leave behind are richer than the soil they ingest. That works! First clause premise, second clause conclusion.

Ok so now we’ve got two conclusions, but only one of these can be our main conclusion meaning one of them is a sub-conclusion that both lends and receives support. If we take a step back, we see that the second conclusion supports the idea that chemical fertilizers should be avoided, meaning that this first conclusion about chemical fertilizers is our main conclusion. Let’s return once more to our old friend Mr. Why Test: Why should the use of chemical fertilizers be avoided? Well because our first premise tells us that fertilizers kill earthworms and our sub-conclusion tells us that a garden rich in earthworms is much more fertile than a garden without them. Now that’s what I call support!

Ok so let’s revisit our main conclusion: “the use of chemical fertilizers should be avoided.” Let’s take a look at our potential answers:

Answer Choice (A) This correctly sums up our premise but is not part of our conclusion.

Answer Choice (B) Again, this refers, correctly to another aspect of our premise, but is not found in our conclusion.

Answer Choice (C) Another answer choice that accurately sums up one of our premises, but not our main conclusion.

Correct Answer Choice (D) This is verbatim the main conclusion we identified. Not much more we need to discuss there. Case closed. But since we’ve still got one more answer choice left, let’s go ahead and take a look.

Answer Choice (E) Ok yet another answer choice that correctly sums up part of our stimulus. In this case this is referring to our sub-conclusion. If you didn’t recognize that this is a sub-conclusion that actually supports our main conclusion, this might be a tempting AC.


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On the Caribbean island of Guadeloupe, a researcher examined 35 patients with atypical Parkinson’s disease and compared their eating habits to those of 65 healthy adults. She found that all of the patients with atypical Parkinson’s regularly ate the tropical fruits soursop, custard apple, and pomme cannelle, whereas only 10 of the healthy adults regularly ate these fruits. From this, she concluded that eating these fruits causes atypical Parkinson’s.

Summarize Argument
The researcher concludes that eating soursop, custard apple, and pomme cannelle causes atypical Parkinson’s disease. Her evidence is a study showing that patients with atypical Parkinson’s disease regularly ate these fruits, whereas the majority of healthy adults did not.

Notable Assumptions
Based on a mere correlation, the researcher assumes that eating certain fruits causes atypical Parkinson’s disease. This means she doesn’t think the relationship is reversed (e.g. having atypical Parkinson’s causes one to be prescribed a diet with such fruits).

A
For many of the atypical Parkinson’s patients, their symptoms stopped getting worse, and in some cases actually abated, when they stopped eating soursop, custard apple, and pomme cannelle.
When the patients stopped eating the fruits, their symptoms stopped deteriorating or actually abated. This strengthens the causal connection between the fruits and atypical Parkinson’s disease.
B
Of the healthy adults who did not regularly eat soursop, custard apple, and pomme cannelle, most had eaten each of these fruits on at least one occasion.
Eating these fruits on one occasion likely isn’t enough to cause atypical Parkinson’s disease, so we don’t care. Besides, we already know there are healthy adults who do regularly eat these fruits.
C
In areas other than Guadeloupe, many people who have never eaten soursop, custard apple, and pomme cannelle have contracted atypical Parkinson’s.
The researcher isn’t claiming that eating these fruits is the only way to get atypical Parkinson’s disease. These people presumably contracted the disease some other way (e.g. genetically).
D
The 10 healthy adults who regularly ate soursop, custard apple, and pomme cannelle ate significantly greater quantities of these fruits, on average, than did the 35 atypical Parkinson’s patients.
This weakens the researcher’s argument. If these fruits cause atypical Parkinson’s disease, then those eating the highest quantities should be most likely to contract the disease. But this tells us those adults actually remained healthy.
E
Soursop, custard apple, and pomme cannelle contain essential vitamins not contained in any other food that is commonly eaten by residents of Guadeloupe.
We don’t care about vitamins. We care about what causes atypical Parkinson’s disease.

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Price: A corporation’s primary responsibility is to its shareholders. They are its most important constituency because they take the greatest risks. If the corporation goes bankrupt, they lose their investment.

Albrecht: Shareholders typically have diversified investment portfolios. For employees, however, the well-being of the corporation for which they have chosen to work represents their very livelihood. The corporation’s primary responsibility should be to them.

Speaker 1 Summary
Price says that a corporation’s primary responsibility is to its shareholders. Why? Because shareholders take the biggest risks. And what risks are those? Well, if the company goes under, the shareholders lose their investment.

Speaker 2 Summary
Albrecht says that a corporation’s primary responsibility should instead be to its employees. Why? Firstly, shareholders usually have many investments (meaning their risk in a single company isn’t all that great). Secondly, an employee’s entire livelihood is at risk if the company goes bankrupt. This implies that employees actually take a greater risk, making them a more important responsibility.

Objective
We need to find a disagreement between Price and Albrecht. They disagree about whether shareholders or employees take the greatest risks, and should therefore be a company’s primary responsibility.

A
corporations have a responsibility to their shareholders
Price definitely agrees with this, but Albrecht never disagrees. Albrecht thinks that shareholders shouldn’t be the primary responsibility of a corporation, but that doesn’t mean the corporation has no responsibility at all towards shareholders.
B
corporations are responsible for the welfare of their employees
Albrecht agrees with this, but Price doesn’t express disagreement. Price doesn’t think that employees are the primary responsibility of a corporation, but that doesn’t mean that corporations have no responsibility towards employees at all.
C
means should be provided for a corporation’s investors to recoup their losses if the corporation goes bankrupt
Neither speaker talks about contingency measures in the case a corporation goes bankrupt. Price and Albrecht’s discussion is about who has the most to lose in a company’s bankruptcy, not what measures could help lower that risk.
D
a corporation’s shareholders have more at stake than anyone else does in the corporation’s success or failure
Price agrees with this but Albrecht disagrees, so this is the point of disagreement. Price claims that shareholders’ investments make them the group with the most to lose in bankruptcy. Albrecht, however, thinks employees risk more with the possible loss of their livelihoods.
E
the livelihood of some of the shareholders depends on the corporation’s success
Neither speaker makes this claim. This is compatible with both Price’s and Albrecht’s arguments, but neither of them discusses one way or another if any shareholders’ livelihoods depend on a company’s success.

3 comments

Despite the enormous number of transactions processed daily by banks nowadays, if a customer’s bank account is accidentally credited with a large sum of money, it is extremely unlikely that the error will not be detected by the bank’s internal audit procedures.

Summarize Argument
The author assumes that if a customer’s bank account is accidentally credit with a large sum of money, the bank will almost certainly detect the error. No evidence is provided for this claim.

Notable Assumptions
The author assumes that a bank’s internal auditing system will almost always detect a large accidental credit, despite the vast number of transactions happening daily. The author likely assumes large credits are dealt with differently than small credits.

A
Banks initially process all transactions using one set of computer programs, but then use a different set of programs to double-check large transactions.
Since banks double-check large transactions, they’re likely to catch an accidental large credit. This shows the quirk in the banking system that makes it so likely such accidental credits are caught.
B
Recent changes in banking standards require that customers present identification both when making deposits into their accounts and when making withdrawals from their accounts.
As far as we know, customers aren’t involved in these accidental credits.
C
Banks are required by law to send each customer a monthly statement detailing every transaction of the previous month.
This doesn’t explain why those large accidental credits would be caught by the bank. If anything, this shifts responsibility to the customer to catch such mistakes.
D
The average ratio of bank auditors to customer accounts has slowly increased over the past 100 years.
Even if that ratio has increased, we have no idea what effect these bank auditors have. It could be that nearly no large accidental credits were caught 100 years ago, and now 10% are. That’s far less than the author argues are caught.
E
The development of sophisticated security software has rendered bank computers nearly impervious to tampering by computer hackers.
We don’t care about hackers. We care about accidental credits, which have nothing to do with hackers.

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