Which of the following distinguishes why conservation sciences might be experiencing slower growth than other research fields? A. Conservation science offers significantly lower salaries than many other plant-related fields.
B. Conservation science has a very large number of people already employed in it.
C. Conservation science does not produce any research that can be used in a practical setting.
D. Conservation science is not a private sector job and depends on scarce public funds.

Correct D) Competitive exclusion

Carrying capacity of an ecosystem may be defined as the total number of organism it can support. Biotic and abiotic factors such as available space, water, food and shelter  act as a limiting factor, which determine how many organism can live within a ecosystem.

The competitive exclusion principle states that two species that compete for same resources cannot stably coexist.

One among the two competitor will always have slight advantage over the other, it leads to extinction of other competitor or lead to an evolutionary shift of the inferior one to a different ecological niche. Therefore, competitive exclusion have least effect on the carrying capacity of an ecosystem.