TOEFL Reading: ETS-TOEFL阅读机经 - 6V744YO6T306KE3PL$

According to paragraph 3 specialists have tried to determine which of the following A. Why Moscow seems to grow naturally in all directions B. How close Moscow was to the geographic population center of the Russian people C. Where the dividing line between the two major dialects of Great Russian was located D. Which of the two major dialects of Great Russian was more commonly used