An ecosystem ________.
a. is a collection of interacting species living in a specific area
b. is a regional grouping of plants, animals and other biotic factors
c. is a grouping of plants and animals that interacts with one another in a way that causes the grouping to die
d. is the total population of a specific kind of plant, animal or microbe and all members of which do or potentially can interbreed and produce young
e. encompasses all the organisms and the physical and chemical environment within an area