[求助]请问斑竹这道题如何理解？

请教：Investing in real estate would be a profitable venture at this time.A survey in House magazine revealed that 85% of the magazine's readers are planning to buy a second home over the next few years.A study of the real estate industry, however, revealed that the current supply of homes could only provide for 65% of that demand each year.

为什么答案选择

Readers of House magazine are more likely than most people to want second homes.

实在搞不清楚，请大师指教。

此题出自新东方GMAT教材逻辑部分第190页question8。问题是Which of the following, if ture, reveals a weaknss in the evidence cited above?

(A)Real estate is a highly labor-intensive business.

(B)Home builders are not evenly distributed across the country.

(c)The nuber of people who want second homes has been increasing each year for the past ten years.

(D)Readers of House magazine are more likely than most people to want second homes.

(E)House magazine includes articles about owning a second home as well as articles about building a second home.

The question is asking for weakness of the evidences of the conclusion.  

The first evidence is "A survey in House magazine revealed that 85% of the magazine's readers are planning to buy a second home over the next few years."

If the magazine's readers are not representative of the general house-buying population, then the original conclusion is questionable.  Answer choice D, "Readers of House magazine are more likely than most people to want second homes," correctly points out this unrepresentative survey sample problem, therefore, is the best answer.