Two years ago, the government of Runagia increased by 20 percent the government-provided pensions paid to Runagians over 65. The aim of the increase was to stimulate the economy in hte rural regions of the country, where most pension recipients live. Statistics, however, show that there has been no increase in economic activity in those regions since then, but that there has been noticeably more spending in the urban areas.

Which of the following, if true, most helps to explain why the increase resulted in the unintended state of affairs described?

A. Until the pesions were increased, many Runagians over 65 in rural regions had been receiving support from their children who live in urban areas.

B. The pension were when the number of people below the poverty level in rural areas of Runagia reached an all-time high.

C. City-dwellers in Runagia rarely travel to rural regions of the country.

D. The Rungagian postal system is so inefficient that it can take up to three weeks for pension checks to reach recipients in rural areas.

E. On average, the pensions were higher in rural than in urban areas before the increase.

The source of this question is GMATprep.

IMO A

D is my answer. The explanation is that if the postal system is so ineffective, old people above 65 are likely to go to the urban areas to pick up their checks.

IMO A

If Runagians already received money from their children, they probably spend the same as before the increase in pension. So, there are no any increase in spending in rural.
In the same time, their children have no need to support their parents so they can spend more in urban.

D, if correct as ehimeme said, it requires another assumption that Runagians will come to spend in urban to spend as a result of delay of mail delivery.
The choice that need another assumption is always incorrect.

thanks for your classic explanation dude!