The correct option is D.
A natural law refers to a description of natural event that has been proved to be true without exception. Such a law usually generalizes a body of observation but can not explain why the observation occur. An example of a natural law is Newton's law of gravity, he observed that an object thrown up usually come down but can not explain the reason behind this observation.
A homogeneous mixture is not considered a pure substance because it can be separated through mechanical and thermal processes. A pure substance, however, cannot be separated.<span>
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Answer:
Evolution
Explanation:
Evolution is the change in habits, hereditary and physical characteristics of a species over various generations in response to environmental conditions. Evolution lead to adaptation, the nature selection of the fittest and elimination of remaining.
Evolution may produce variety and diversity in response to mutation, genetic drift and other genetic variation. These changes may pass to offspring and may express them more in one group of population.
Evolution also explain the unity among organisms by explaining their shared characteristics. This refers to their common ancestors.
The mechanism that affected the gene pool of the immigrants that entered the United states Through Ellis Island is Gene flow.
Gene flow involves the movement of genes or alleles between interbreeding populations of a particular species. In other words it is the movement of genes from one population to another population. Actually it may be an important aspect of evolution; evolution can occur as a result of genes being transferred from one population to another. Gene flow occurs when there is migration, since the loss or addition of people can easily change pool frequencies even without no other evolutionary mechanisms operating.
Human because human is the only organism on the list!