What Is the Greatest Problem That the Human Population Will

What is the greatest problem that the human population will face if we fail to have a greater understanding of ecology and environmental science?

A) We will have a lack of understanding about the problems that the human population poses to the health of the biosphere.
B) We will have a lack of understanding about the ability of the human population to obtain additional resources from the environment.
C) We will not understand how to expand human society into currently uninhabited areas on the planet.
D) The human population will start to decline in size.
E) The human population will go extinct in the near future.