The answer would be D hope it helps
Urban sprawl..............
Answer:
C) Oxygen
Explanation:
As the Earth cooled, a primitive atmosphere was created by the out-gassing of early volcanoes. The early atmosphere contained no oxygen and would have been toxic to human beings, as well as most other life on Earth today.
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A host cell infected by a virus will activate the adaptive immune response through white blood cells that are called as lymphocytes.
There are two types of responses through cells: antibody responses and cell mediated immune responses. These responses are occur by different types of classes of white blood cells those are called as B cells and T cells.
These T lymphocytes use chemical messenger to activate other immune system cells so that the adaptive immune system can activate. It detect the infected cells and destroy the cell.
Antibody is a blood protein that is produced in body in response to the specific antigen.
To learn more about Antibody here
brainly.com/question/13011942
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