Continental climates are characterized by very hot summers and very cold winters. Rob would experience a wide array of temperatures and changes during a year and a very distinct change in weather from one season to the next. In this type of climate, he could experience a truly hot summer, rainy fall, sunny and green spring, and very white and cold winters.
The answer is D. The question asks how different cultures influenced each other so that rules out options A & B. Option C is about the environment being destroyed, and that really has nothing to do with foreign influence.
