An organism’s niche

a. the range of physical and biological conditions in which an organism lives and the way in which it uses those conditions.
b. all the physical and biological factors in the organism’s environment.
c. the range of temperatures that the organism needs to survive.
d. a full description of the place an organism lives.

A, the range of physical and biological conditions in which an organism lives and the way in which it uses those conditions.

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.