The correct answer is - A. replacing natural vegetation with cultivated crops.
The natural vegetation is perfectly adapted to a certain environment, and it is also able to keep the soil tight with its roots, so the erosion is minimal.
When the natural vegetation is replaced by cultivated crops, than a problem occurs in the erosion of the soil. That is because the cultivated crops, in general, do not have root systems that are as strong and widespread as the natural vegetation, thus the soil becomes loosened up, so it is much easier to be eroded.
Answer: North Dakota
Explanation: The geographic center of North America is set near Rugby, North Dakota 48°10′N 100°10′W, though this has no official status.
<span>d. a rift between the leadership of the Eastern Orthodox Church in Turkey and the Armenian Orthodox Church.
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