Nice set of questions Mike!

I believe in general Strengthen questions are a bit easier than the notorious Weaken and assumption questions. A blog on those 2 types would be great!

gracias!

The psychologists conclusion: signs of civilization remind drivers of their responsibility to slow down.

A. Does not strengthen. The conclusion has nothing to do with the ability of the cars; rather, it focuses on the human response to signs of civilization.

B. Bingo. A cultivated field is a sign of civilization and produces slower driving. The field of flowers lacks that sign, and thus fails to produce a cautionary response.

C. This is not about the human response to signs of civilization, but minutia about traffic. Doesn't strengthen.

D. We're not concerned with whether the buildings are tall or not. Although seeing the buildings (signs of civilization) produces the desired result (slowing down), we're not trying to differentiate between the signs of civilization. We're trying to differentiate between signs of civilization and the LACK of signs of civilization. Not this one.

E. Speeding where signs of civilization are abundant would weaken the psychologists hypothesis.

Mike@Magoosh wrote:Studies have shown that highway drivers are less likely to drive at speeds greater than the posted speed limit if houses or buildings are in some way visible from the road. Assuming similar car, road and traffic conditions, highway drivers are more likely to drive at speeds in excess of the posted speed limit if the natural surroundings are not interrupted by buildings. Psychologists hypothesize that seeing signs of civilization reminds drivers of their responsibility to the safety of their fellow humans, thus making them more likely to obey the posted speed limit.

Which of the following, if true, most strongly supports the psychologists' interpretation of the study?

(A) People who live in sparsely populated areas are more likely to buy cars that can drive well in excess of any speed limit.
(B) Highway drivers passing a large plowed and cultivated field are more likely to obey the speed limit than those passing large field of wild flowers.
(C) Traffic tends to be more congested around towns and cities.
(D) Drivers are equally likely to obey the speed limit whether driving past a town with or without tall buildings.
(E) Highway police officers are more densely located close to towns and cities, and therefore most citations for speeding are issued in these locations.

For a discussion of GMAT CR Strengthen the Argument questions, as well as the OA & explanation to this particular question, see:
https://magoosh.com/gmat/2013/gmat-cr-st ... -argument/

Mike