A neighborhood in downtown Pittsburgh has experienced a sharp increase

Question

A neighborhood in downtown Pittsburgh has experienced a sharp increase in residential break-ins. The point of entry is always a basement window that is surrounded by bushes or some other object. The neighborhood watchgroup believes these entry points are chosen because they are difficult to view from public thoroughfares such as adjacent streets or back alleys and has recommended trimming all large hedges that obscure basement windows.

Which of the following contains a flaw in logic that most closely parallels the one contained in the passage?

(A) People who like rabbits can't possibly like dogs because dogs hunt rabbits.

(B) Martha's geraniums always die; she must be buying weak geraniums.

(C) When it is dark Sandra can't drive. Sandra is not driving, so it must be dark.

(D) if priests oppose murder, then all religions must oppose murder.

(E) Highly trained dogs can track and this dog can track, therefore it must be highly trained.

KarishmaB · Accepted Answer

The logic of the argument is this - Break ins are happening in houses. It is because of a weakness in the house itself - hidden basement window. Clear up the window to avoid break ins.

Option (B) reflects the same flaw in logic: (B) Martha's geraniums always die; the reason must be in a weakness in her geraniums. Presumably, if she buys stronger geraniums, they will survive.

None of the other options are even close.

cycaroline47 · Answer

Reasoning in the stimulus is  .

Event A in the stimulus is "break-in through the basement (windows)", feature is "difficult to view"

Event A in the answer choice is "geraniums die", feature is "geraniums are weak".

GMAToverPUBG · Answer

The watchgroup believes(or blames) that the break-ins are happening because of the windows and hedges. While thats the watchgroup job to protect. So the flaw in the argument is  blaming the feature rather than the one who is responsible

(A) People who like rabbits can't possibly like dogs because dogs hunt rabbits. -  Irrelevant because there is no relation between windows and Watchgroups.

(B) Martha's geraniums always die; she must be buying weak geraniums. -   Correct.  It could be Martha is not taking care of the geraniums. Since Martha is responsible, no one should blame the geraniums.

(C) When it is dark Sandra can't drive. Sandra is not driving, so it must be dark. -  Irrelevant - This shows opposite co-relation, no relevance.

(D) if priests oppose murder, then all religions must oppose murder. -  Shows a flaw of herd instinct. Not what we are looking for.

(E) Highly trained dogs can track and this dog can track, therefore it must be highly trained.  Similar to C this shows opposite co-relation. No relevance.

Hence, B.

bnairsurya · Answer

It's all upto presumption here!

If the public can't see, then the theives can't also see. Hence option D is best suited.
And the other is what Karishma said.

gullyboy09 · Answer

Hi  KarishmaB , but what's the flaw in the argument here? It seems to me a reasonable recommendation.

guddo · Answer

A neighborhood in downtown Pittsburgh has experienced a sharp increase in residential break-ins. The point of entry is always a basement window that is surrounded by bushes or some other object. The neighborhood watchgroup believes these entry points are chosen because they are difficult to view from public thoroughfares such as adjacent streets or back alleys and has recommended trimming all large hedges that obscure basement windows. 
 
Which of the following contains a flaw in logic that most closely parallels the one contained in the passage?

The watchgroup sees that the broken-into windows are hidden from public view and concludes that the windows were chosen because they were hidden.  The flaw is treating one possible explanation as if it must be the explanation . Maybe those windows were chosen for some other reason, such as being easier to open or structurally weaker.

(A) People who like rabbits can't possibly like dogs because dogs hunt rabbits.

This is not parallel. It makes an unsupported incompatibility claim, not a mistaken causal explanation.

(B) Martha's geraniums always die; she must be buying weak geraniums.

This is correct.  The argument observes a repeated result and jumps to one possible cause. Martha’s geraniums may die because they are weak, but they may also die because she overwaters them, gives them too little sunlight, or neglects them. This mirrors the original flaw: hidden windows may be chosen because they are hidden, but another explanation is also possible.

(C) When it is dark Sandra can't drive. Sandra is not driving, so it must be dark.

This is a conditional flaw, but it is not as close. The original is mainly a causal-explanation error, not simply “if X then Y; Y, so X.”

(D) If priests oppose murder, then all religions must oppose murder.

This is an invalid generalization from one group to all groups, not parallel.

(E) Highly trained dogs can track and this dog can track, therefore it must be highly trained.

This is also a conditional-style flaw, but it does not match the causal explanation pattern as well as B does.

Answer: (B)

egmat · Answer

Hi gullyboy09,

You're right that the recommendation  sounds  practical, and that's exactly what makes the flaw easy to miss. The question isn't asking whether trimming hedges is a good idea - it's asking you to spot the  leap in reasoning  the watchgroup makes.

Here's the leap. All they actually observed is a pattern:

- Break-ins keep happening at basement windows.
- Those windows happen to be hidden by bushes.

From that pattern alone, they jump to  one specific cause : "these windows are chosen  because  they're hard to see from the street." Notice the word "because" - they've decided the concealment is the reason, then built the fix (trim the hedges) on top of that single assumed cause.

But they never ruled out other explanations. Maybe basement windows have the weakest latches. Maybe they're simply the easiest to climb through. If any of those is the real reason, trimming hedges does nothing.  The flaw is assuming one cause for an observed effect without eliminating the alternatives.

Now look at the discussion's pick,  (B) : "Martha's geraniums always die; she must be buying weak geraniums." Same move exactly - an observed effect (dead plants) blamed on one assumed cause (weak geraniums), ignoring overwatering, bad soil, too little light. That's why (B) parallels the passage.

To feel the structure, try turning the same sentence:

- "My phone keeps dying, so the  battery must be defective " - what about leaving  50  apps open? Same flaw.
- Now change it to "My phone dies  only  when the battery is old, and it's dying, so the battery is old" - that's a  different  flaw (matches C/E, not the passage).

Keep your eye on that one-cause jump, and (B) clearly stands out.

Answer: B

A neighborhood in downtown Pittsburgh has experienced a sharp increase

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A neighborhood in downtown Pittsburgh has experienced a sharp increase

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