Which is correct?

"Overpopulation refers to a condition by which the population density enlarges to a limit that provokes the environmental deterioration. ...................................................................... . Throughout history, populations have grown slowly despite high birth rates, due to the population - reducing effects of war, plagues and high infant mortality. During the 750 years before the Industiral Revolution, the world's population hardly increased, remaining under 250 million."

A- The term population density denotes the number of inhabitants in a specific area.
B- However, it has been observed that after a certain level of development its population increases again.
C- Nevertheless, concern about overpopulation is relatively recent in origin.
D- By the beginning of the 19th century, though, the world population had grown rapidly.
E- Overpopulation does noot depend only on the size or density of the population.

I think it is C or E but I still can't find the correct answer. Which one is correct and why? Can you help me?