Well it could be A but I think D is better. While A is true D is more specific to how humans are disrupting the cycle.
One-celled (single-celled)
organisms, however, tend to be different from those with many cells.Larger celled organisms <span>such
as plants and animals, have a higher degree of specialization where the cells
work together and function to create a living organism.</span>
What viral disease now thought to only exist inside a laboratory caused the death of many American Indians after europeans arrived in north American?
smallpox
Explanation:
.
Leaves conduct photosynthesis, which converts energy from the Sun into chemical energy