The population of Dorthhampthon is expected to grow at an average rate

Question

The population of Dorthhampthon is expected to grow at an average rate of 6 percent a year in the coming decade. Many of Dorthhampthon’s residents raised concerns regarding the effect of this growth on the recreation areas in the city's center, yet the Dorthhampthon mayor's office claims that such growth will not threaten the existence of any of these.

Which of the following, if true, will most strengthen the claim of the mayor's office?

(A) By attracting more new citizens, Dorthhampthon's municipality will be able to increase its budget for the development of recreation areas.
(B) Dorthhampthon's municipality intends to increase the city's jurisdiction, allocating new areas for parks and recreation in its surroundings.
(C) Dorthhampthon's ratio of park area per resident is about half that of similar cities in the region.
(D) The new housing projects in central Dorthhampthon are planned to replace lower buildings in older complexes.
(E) Annual population increase of 6 percent a year poses a significant challenge to the city's infrastructure.

bb · Accepted Answer

This was a very very tough question with a very subtle detail. It may be even too subtle but it illustrates importance of reading attentively and precisely. 
Thank you,
BB.

Official Explanation by examPAL:

What’s important to understand in the argument is that the mayor claims that the population increase won’t affect the existing recreation areas, not only recreation areas in general.

Therefore, (A) and (B), which might seem relevant since they discuss new recreation areas, are not relevant – since they don’t address the concern that the exiting areas will be harmed.
(C) is completely irrelevant.
 (D) directly addresses the issue: if the new housing replaces existing housing, it won’t affect existing recreation areas. 
(E) is irrelevant and weakens the argument: it describes a negative effect of the population growth.

jbrandl1 · Answer

The population of Dorthhampthon is expected to grow at an average rate of 6 percent a year in the coming decade. Many of Dorthhampthon’s residents raised concerns regarding the effect of this growth on the recreation areas in the city's center, yet the Dorthhampthon mayor's office claims that such growth  will not threaten the existence  of any of these.

We need to find a reason supporting the claim that population growth in the city "will not threaten the existence" of the recreation areas.
We want the current recreation areas to remain recreation areas.

Which of the following, if true, will most strengthen the claim of the mayor's office?

(A) By attracting more new citizens, Dorthhampthon's municipality will be able to increase its budget for the development of recreation areas.
 If the budget is higher, new areas could be built and existing areas could be improved.
While this sounds good, a higher budget doesn't directly protect the space.

(B) Dorthhampthon's municipality intends to increase the city's jurisdiction, allocating new areas for parks and recreation in its surroundings.
 This option discusses the development of new areas, not the protection of existing areas. I think that disqualifies this answer choice.

(C) Dorthhampthon's ratio of park area per resident is about half that of similar cities in the region.
 This does nothing for the argument that population growth will not threaten the existence of the recreation areas.

(D) The new housing projects in central Dorthhampthon are planned to replace lower buildings in older complexes.
  Looks good.  By stating that the growing population will be housed on the current building area (no new area will need to be converted to building area), this answer choice supports the claim that the existence of the recreational areas is not threatened. If the growing population can be housed without additional building area, the current recreational area is probably safe. While this does depend on taking "existence" quite literally, this is the best choice here.

(E) Annual population increase of 6 percent a year poses a significant challenge to the city's infrastructure.
 This does not offer any support for the argument that population growth will not threaten the existence of the recreation areas. In fact, the answer choice probably weakens the city's argument.

Therefore, answer  D  looks like the correct answer choice.

techloverforever · Answer

Prethinking :
the mayor claim's that the expected growth won't threaten the existence of recreation area. 
Hence information of a separate provision made by the city to incorporate such a rise in population can help strengthen the argument.
POE:
A) By attracting more new citizens, Dorthhampthon's municipality will be able to increase its budget for the development of recreation areas.  Irrelevant : as the argument talks about the area and not funds 
(B) Dorthhampthon's municipality intends to increase the city's jurisdiction, allocating new areas for parks and recreation in its surroundings.  Wrong :Claims are made of the existing areas and not the new ones 
(C) Dorthhampthon's ratio of park area per resident is about half that of similar cities in the region. Irrelevant : as no comparison is made with the other cities  
(D) The new housing projects in central Dorthhampthon are planned to replace lower buildings in older complexes.  Perfect as new houses replace the old one having lower buildings--> Correct 
(E) Annual population increase of 6 percent a year poses a significant challenge to the city's infrastructure.  Irrelevant weakens the claim
 
Option D

JonShukhrat · Answer

Stimulus:  Residents are worried that population increase may threaten the recreation areas in the city's center. Mayor’s office claims that it is not.

What we need to strengthen is the claim of mayor’s office.

Claim:  such growth will not threaten the existence of any of these (recreation areas in the city's   center  ).

We need a piece of information that will support this claim.

A.  By attracting more new citizens, Dorthhampthon's municipality will be able to increase its budget for the development of recreation areas.
This answer choice doesn’t clarify what will happen with the recreation areas in the center. We are not sure whether increased budget will be spent on the recreation areas in the center. It can very well be spent on moving this area to the suburbs.

B.  Dorthhampthon's municipality intends to increase the city's jurisdiction, allocating new areas for parks and recreation in its surroundings.

Since this answer choice talks about suburbs, but not the center, it is irrelevant.

C.  Dorthhampthon's ratio of park area per resident is about half that of similar cities in the region.
We don’t know whether this ratio will be maintained or improved or worsened because of population increase.

D.  The new housing projects in central Dorthhampthon are planned to replace lower buildings in older complexes.
If new housing projects don’t require additional land area, but replace old buildings, then there is no threat for the recreation area in the center. Hence D strengthens the claim and explains what the mayor’s office meant.

E.  Annual population increase of 6 percent a year poses a significant challenge to the city's infrastructure. 
The claim is weakened to some extent now.

Hence  D

thelastskybender · Answer

I think the phrase  'effect of this growth on the recreation areas in the city's center'  is a bit ambiguous, as it could refer either to the physical infrastructure of the recreation areas or to the population pressure on them, depending on how you interpret it. The conclusion that growth will not threaten the existence of any of these areas might also be understood in two ways — it could mean the physical survival of the recreation areas, or it could refer to their continued availability as well-maintained, uncrowded spaces. So, if we consider the issue from the perspective of population load (i.e., how crowded it gets), option B might also be a valid answer. Let me know what you think  bb

LightCar · Answer

I totally disagree with your answer, and I am confident this is  purely your opinion  and not "OA"/"Expert" level analysis for sure. I feel there should be more depth to your explanation, if you want to prove otherwise. While you have given one reason to claim your answer is right, I have many reasons to prove that your answer is debatable at best, but  not  the strongest point for the mayor's statement, for sure.

1. First, let's go through the para 
 
This statement just says the existing population has some concern regarding the estimated population growth in the near future on the recreational land. They have not mentioned what the concern is.

2. Second, lets go through your opinion 
 
I wouldn't say this statement is wrong. But I wouldn't say that this statement is right too. But I would definitely say that it is uncertain. One can not confidently say that this point would strengthen the Mayor's office from the information provided.
To come to this conclusion you have assumed a couple of things.
1. The concern regarding the growth of population ( not described in the passage ) is the loss of recreational land.
2. For Assumption 1 to hold true, you have assumed 2 more things, that is
 - the city area is completely filled, with either housing or recreational land, and there is no free/empty land to build new housing.
 - the existing housing/non-recreational land is insufficient to accommodate the growing population in the near future. In other words, you assumed that the  population_that_can_be_accomodated/area  is already saturated, and hence, to accommodate the growing population, the lower buildings need to be replaced.

Clearly, your answer is based purely on assumptions, but not on implications.

While one of reasons that the population is concerned regarding the growth in population is loss of recreational land, it could, in reality, be anything. For example:
1. The recreational areas are not sufficient to accommodate the growing population, requiring more recreational areas to be built.

3. Finally, lets evaluate one of your statements based on the above statements: 
 
This statement is more than sufficient to prove A and B. The mayor does claim that the population increase will not affect the existing areas because:
 Option A : Increase in population -> increase in taxes -> increase in budget -> develop more recreational areas in the city to accomodate the growing population ->  no overcrowding/insufficiencies (no effect) in the existing recreational areas in the city center. 
 Option B : Increase in city's jurisdiction -> increase in land -> increase in recreational areas/parks etc (and also manages growing population better) ->  no overcrowding/insufficiencies (no effect) in the existing recreational areas in the city center.

To conclude, option D is the only one based on assumptions, while the other two are based on implications. A,B are more direct and stronger to prove the mayor's office statement.

The main reason for me to believe A,B are more appropriate is that whenever there is going to be a major influx in population in any city, the recreational land is usually untouched, because everyone views these areas as important places in a city. However, the govt looks for massive expansion naturally.

SeedWasp · Answer

Option D is all about "central" Dorthhampthon. How can it be correct...what about the rest of Dorthhampthon?

egmat · Answer

Hi SeedWasp,

Good eye for scope, but here the "central" wording in D is actually what makes it the winner, not a weakness.

Go back to the mayor's exact claim. The residents raised concerns about  "the recreation areas in the city's center,"  and the mayor says growth  "will not threaten the existence of any of these."  The word  "these"  points straight back to the recreation areas  in the center  - not anywhere else in Dorthhampthon.

So the argument is already limited to the city center. We aren't asked to protect recreation areas in the rest of the city, because no one - not the residents, not the mayor - was talking about those. The claim we're strengthening lives entirely in the center.

That's why  D  fits perfectly:
- The worry is that housing a growing population will eat up the  central  recreation land.
- D says the new housing in  central  Dorthhampthon replaces older, lower buildings - i.e., the extra people are absorbed by building  taller on land already built up .
- So the central recreation areas don't have to be sacrificed. Existence is protected - exactly where the claim applies.

Turn one knob to feel it:  imagine the mayor's claim had instead been  "growth will not threaten any recreation area in all of Dorthhampthon."Now  your objection would be fair - D, covering only the center, would leave the rest unaddressed. But as written, the claim never reached beyond the center, so D covers precisely the ground it needs to.

Matching the scope of the conclusion is the skill here - D isn't too narrow; the claim itself was narrow.

Answer: D

The population of Dorthhampthon is expected to grow at an average rate

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The population of Dorthhampthon is expected to grow at an average rate

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