Answer:
naturally living organisms
Edit
Viruses reproduce within the living cells of the host and use the cellular machinery to synthesize their own genome and other components. To gain entry into cells, they have developed a variety of mechanisms to introduce their genes and proteins into host cells.
Famine- High population means more mouths to feed
Disease- Diseases usually spread more quickly with people who live closer( as it can just move from one person to the other)
War- People like to fight for land, resources, money, etc. And having more of those things mean they are more able to support families, communities, and more.
(Hope this helps a little)
It is student A .
It contains the study of plants and soil
Answer:
the food that we eat are used up by the cells to perform different activities such as metabolism.