Recently in City X, residential developers have stopped buying land,

This argument relate to number and statistic. I agree with gmatpill that, if the question is "Weaken", the answer choice will be C.
However, the question is "flaw". Choice A take this job better. Choice A clearly shows that because the lands were hold up because of one policy. So, the construction developers did not buy lands any more. Instead, they'll wait for the expire date of above policy.

Choice C makes a trap that the decrease in percentage will cause the decrease in number.

in (A) " several " is mentioned, but in premise it's talking about the overall condition; how can several can refer to the general/overall situation?

Dear tuanquang269 and GMATPill,
Please refer to the official explanation by Manhattan experts. The boldface seems to contradict what you thought of the answer C which can be true if the question is "weaken". For me, it is so vague to differentiate between "flaw" question and "weaken" question!

The conclusion of the argument is that "there must be fewer new residents moving to City X than there were previously." Why? The author observes several factors (e.g., developers not buying land, contractors without work, electricians working predominately on existing homes) and then assumes that fewer new homes are being built specifically because fewer new residents are moving to this city. We are asked to weaken this conclusion; one way to do so would be to find an alternate explanation for the observation that fewer new homes are being built right now.

(A) CORRECT. This suggests that there might be another reason for the decline in home construction: the supply of available housing has been increased through the release of a glut of previously built homes.

(B) The size of homes, by itself, does not address the reason(s) fewer homes are being built right now in City X.

(C) The author's conclusion is specifically that “fewer new residents” are moving to City X. The cited population increase might have been due to babies born to existing residents this year. Though this choice is tempting, we cannot conclude that it means more new residents are moving into the city.

(D) If materials cost less, it seems more likely that any decrease in new home construction could be attributed to the stated causes.

(E) The sales level of cars and boats does not address the reason(s) fewer homes are being built right now in City X.

Dear tuanquang269 and GMATPill,
Please refer to the official explanation by Manhattan experts. The boldface seems to contradict what you thought of the answer C which can be true if the question is "weaken". For me, it is so vague to differentiate between "flaw" question and "weaken" question!

The conclusion of the argument is that "there must be fewer new residents moving to City X than there were previously." Why? The author observes several factors (e.g., developers not buying land, contractors without work, electricians working predominately on existing homes) and then assumes that fewer new homes are being built specifically because fewer new residents are moving to this city. We are asked to weaken this conclusion; one way to do so would be to find an alternate explanation for the observation that fewer new homes are being built right now.

(A) CORRECT. This suggests that there might be another reason for the decline in home construction: the supply of available housing has been increased through the release of a glut of previously built homes.

(B) The size of homes, by itself, does not address the reason(s) fewer homes are being built right now in City X.

(C) The author's conclusion is specifically that “fewer new residents” are moving to City X. The cited population increase might have been due to babies born to existing residents this year. Though this choice is tempting, we cannot conclude that it means more new residents are moving into the city.

(D) If materials cost less, it seems more likely that any decrease in new home construction could be attributed to the stated causes.

(E) The sales level of cars and boats does not address the reason(s) fewer homes are being built right now in City X.

By the way, for me, I chose B as the answer. B suggests that one bigger house can accommodate more people; therefore, it shows a reasoning flaw or weaken the conclusion (whatever if it's true) that "There must be fewer new residents moving to City X than there were previously."

Please show me what's wrong with my thought. Thank you so much!

Based upon the context of choice A, I thought "housing developments" means "house developers".

Had option A included "houses" or "residencies" or "homes" instead of "Housing developments", I would have definitely preferred A over B. These are the moments when your months and months of practice goes into waste.

The only reason: Being a non native speaker

Recently in City X, residential developers have stopped buying land, contractors are going without work for longer periods, and specialty workers such as electricians are relying more on less lucrative, existing-home remodeling jobs. There must be fewer new residents moving to City X than there were previously.

1> May be more residents are moving out so space (and everything that comes with it) is available for residents who are moving in.

Which of the following, if true, indicates a flaw in the reasoning above?

This year several housing developments have gone on the market after being held up for months by legal red tape.

Here the Para is saying that there is decrease in land buying...blah blah.. something..
On Basis of this, author concluded that there will be fewer new residents to city X.

My pre thinking. Ok, there are no new projects. But, there might be many (already) completed projects (which are vacant for new residents)
Option A: This is in same lines with my prethinking. After being held up for several months, Already completed projects came to the market

Please let me know if my understanding is not correct

Your understanding is spot on.
Just make sure, you are also proving that the remaining 4 options are Incorrect. This is to ensure you do not fall into a trap answer, especially on 700+ questions.
Pre-thinking will get you through most of the questions, but sometimes, what you think isn't present in any of the answer choices, so my 2 cents would be to also practice rejecting other answer choices on solid reasoning.

Best of Luck mate!

DmitryFarber chetan2u

Please provide your reasoning to eliminate option B

Though I chose A by prethinking I still could not eliminate B on a solid ground.
Please provide your reasoning

My reasoning to eliminate B -
We do not the extent of the increase in size. I mean the increment could be in anything but more availability of rooms?

Please share your reasoning

Posted from my mobile device

I think B is wrong because it is out of scope in terms of time. The question talks about "Recently in City X, residential developers have stopped buying land etc. etc." However, B talks about a much longer period of time ("The average size of a new home has increased significantly over the past several years") and therefore can't account for the recent changes.

Notice that A has the correct time scope: "This year several housing developments have gone on the market after being held up for months by legal red tape."

This question is Flawed .

In my view all options are Wrong.

Flaw in the correct answer A is that it mentions several housing ( which can be two or three housings, we cant assume 5000 or 10000 housings.)
Also there is no mention of This year in the question as compared to previous year, It Could be This month to previous month also.

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