An oligarchy is a government run by a small, conservative faction.

Question

An oligarchy is a government run by a small, conservative faction. Often, oligarchies consist of families such as the Royal Family in Saudi Arabia. Like the Royal Family in Saudi Arabia, no one person in an oligarchy has the power to make a particular investment. Therefore, risky investments are never made by oligarchies.

The conclusion of the argument is valid if which one of the following is assumed?

A) Not all oligarchies are fun by families.
B) The Royal Family in Saudi Arabia has never made a risky investment.
C) Conservative governments rarely make risky investments.
D) Only liberal governments make risky investments.
E) Only individuals make risky investments.

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imfinetyandu · Answer

Bunuel  What's the official answer to this question?

Bunuel · Answer

The OA will be automatically revealed on Saturday 31st of August 2024 01:30:51 AM Pacific Time Zone

Meanwhile you are most welcome to post your solution.

singhansh13 · Answer

The argument suggests that because no one person in an oligarchy has the power to make a particular investment, risky investments are never made by oligarchies. To support the conclusion that "risky investments are never made by oligarchies," the argument needs to assume something about the nature of who makes risky investments.
- A) Not all oligarchies are run by families.
 This doesn't directly address the reasoning in the argument about risky investments.

- B) The Royal Family in Saudi Arabia has never made a risky investment.
 This is too specific and does not generalize to all oligarchies.

- C) Conservative governments rarely make risky investments.
 This suggests a tendency but does not guarantee that risky investments are never made.

- D) Only liberal governments make risky investments.
 This could imply that since oligarchies are conservative, they would not make risky investments. However, it doesn't directly address the role of individuals versus governments.

- E) Only individuals make risky investments. 
 If only individuals make risky investments, and no individual in an oligarchy has the power to make a particular investment, then oligarchies as a whole would not make risky investments. This assumption directly supports the conclusion.

Correct Answer: E) Only individuals make risky investments.

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Bunuel · Answer

Official Explanation

If risky investments are never made by oligarchies because no one person has the power to make a particular investment, then it must be the case that only individuals make risky investments. The answer is (E).

rajkoushik17 · Answer

In the premise it has been specifically quoted that "Like the royal family in Saudi Arabia". Negating option B would say Royal Family in Saudi Arabia made a risky investment and the conclusion has the word "never" therefore negating Option B would collapse the argument. Then why the answer isn't option B, please explain.

guddo · Answer

The key is that this is a  sufficient-assumption  question, not a necessary-assumption question. So the negation test does  not  apply.

(B) may be consistent with the conclusion, and its negation may contradict the conclusion, but assuming (B) still does not prove that  all oligarchies  never make risky investments. It tells us only about the Saudi Royal Family.

(E), however, supplies the missing rule: if  only individuals can make risky investments , and no individual in an oligarchy has the power to make an investment, then an oligarchy cannot make a risky investment.

So (E) actually makes the conclusion logically follow.

egmat · Answer

Hi rajkoushik17,

Good instinct to reach for the negation test, but here it's the wrong tool, and that's the whole knot.

Notice the exact stem:  "The conclusion of the argument is valid  if  which one of the following is assumed?"  That phrasing asks for a  sufficient  assumption - a statement you  add in  to make the conclusion logically follow. The negation test is built for  necessary  (required) assumptions, a different question type. So when you negate B and watch the argument wobble, you're running the right procedure on the wrong kind of question.

What you actually want here is:  which choice, when plugged in, forces the conclusion to be true?

Why E does that.  The premise says  "no one person in an oligarchy has the power to make a particular investment."  Add E -  "Only individuals make risky investments."  Now the chain is airtight: risky investments come only from individuals, no individual in an oligarchy can invest,  therefore  an oligarchy can never make a risky investment. Premise - conclusion, guaranteed.

Why B isn't it.  Look at how Saudi Arabia enters:  "Like the Royal Family in Saudi Arabia..."  - it's an  illustration  of the premise, not a link in the logic. One example about one family can't make a universal  "never"  conclusion follow. It's too specific to bridge anything.

Quick contrast to lock it in:

-  Necessary  stem - "which is  required ?" - use the negation test.
-  Sufficient  stem - "conclusion is  valid if  assumed" / "which, if true,  proves  the conclusion?" - plug it in and check the chain.

Spot the stem first, and B stops being tempting.

Answer: E

PrimeMat · Answer

I was confused about B and E. The key distinction is that B follows logically from the arguments and the conclusion in the passage. It is NOT an assumption on which the above passage is based. E however is an important assumption that bridges the gap between the 2nd to last and the last line.

An oligarchy is a government run by a small, conservative faction.

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An oligarchy is a government run by a small, conservative faction.

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