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

Option (e).

Explanation:

Ecosystem may be defined as the system that includes all the things of the particular area. Two main component of ecosystem are living organism and non living environment.

Living component includes all the living organism. Non living component includes the chemical environment and physical environment like temperature and pressure. The interaction of both the component is involved in the ecosystem.

Thus, the correct answer is option (e).

"do a testcross with a homozygous recessive plant."