I believe its large blue vessel also known as vena cava
Answer:
D. Take many thousands of years to form
Explanation:
James Hutton discovered thin layers of sediments on his flooded farm and he concluded that strata was part of the earth surface in the past and thus takes many thousands of years to form.
This led to the principle of uniformitarianism which states that the geologic processes now are the same with the ones in the past.
Virus
It needs to hijack the cells genetic machinery to reproduce
B. Cells are the Smallest unit in a living thing capable of preforming all life processes
