In the early days of agricultural development, insect problems were rarely encountered. This problem arises with the development of agriculture-only one kind of grain is planted on a large area of land. Such planting methods have provided a surge in some insects. Advantages: Obviously, a wheat-eating insect multiplies much faster in farms that specialize in wheat than in other farms. Which of the following does not explain the above statement? ? ['A disease caused by beetles sweeps away sycamore trees on both sides of a city street.', 'The pattern of controlling the suitable area of the habitat of a certain species of organism in accordance with the law of natural development.', 'Species that have migrated to new areas have flourished as they have fled from their natural enemies to control it.', 'Poplar pests will have limited reproduction speed in poplar forests mixed with other trees.']