All the members of a specific species that live in an area are a population.
It should be natural selection since there is no external influence implied. (like environment or genetic mutations.)
Answer: <span>B) Plant trees along canals and roadways on their property to filter runoff and prevent soil erosion
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The roots of trees help prevent the soil from being easily eroded by holding the soil in place and taking up the water. The other choices, A, C, and D would cause further erosion by removing objects that would stop the rain or by aiding erosion due to gravity.
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Answer:
The biologist is studying about the ecological community.
Explanation:
The ecological community refers to the community in which population of different types of species survives together. As the biologist is observing about the interaction of different populations of Pennsylvania region, it can be inferred that the he is studying about the ecological community of Pennsylvania region.
The population surving in the community interact with each other through different modes of interaction. It may either parasitic, or mutual, or competitive or predication or commercialism.
I think is the first and second!!