~ C. Population
Population is all the inhabitants of a particular town, area, or country.
The answer could be either B or D. Both are important for marine biology. I would have to say D is the best answer though!
Every person has their own part to play or if you want to get scientific then a niche. And if somebody doesn't do their job then it could slow everyone else down. Maybe I don't fully understand the question, But I hope its right.
The correct answer is: post-industrial community (society).
Post-industrial community is the society in which service sector brings more wealth than the manufacturing sector of the economy. In this kind of society, knowledge is valuated and producing ideas is the main way to grow the economy of that society.
4: a species is a group of interbreeding natural populations that are reproductively isolated from other such groups. Process of Speciation. The process of speciation is a 2 stage process in which reproductive isolating mechanisms arise between groups of populations.