The following table shows the observations made by some students in a science class. Determine the levels of biological organization described by each student, 1-4.

What is a population? a. all the members of the same species living in the same ecosystem at the same time b. the number of a species living in the same ecosystem over a period of time c. the total number of organisms living in an ecosystem at a point in time d. all the members of a food web in the same ecosystem