The best answer is C
The process by which a cell divides is called mitosis. It results in two daughter cells that are genetically identical to each other and to the original cell.
Multicellular organisms, depend on mitosis for growth and repair. Organisms repair some of their tissues using mitosis to regenerate new cells. Not all cells undergo mitosis at the same rate. In man, brain cells are much more difficult to regenerate than cheek cells which are constantly being replaced.
Answer:
Acid rain is caused by emissions of sulphur dioxide and nitrogen oxide, which react with the water molecules in the atmosphere to produce acids.
Smog is an abiotic factor affecting a biotic factor(s).
This is because smog isn't a living organism so it is abiotic while humans are multicellular organisms so therefore, they are biotic factors.
Smog has a negative effect on many biotic factors.
The first questions answer is a community.
The second questions answer is a desert.
Hope this helps.