Which statement about ecosystems is true?

A) Chemicals flow through ecosystems in a one-way direction and are not recycled.
B) Energy continually cycles through an ecosystem.
C) Some organisms can produce their own food and these organisms form the base of the food chain.
D) Within an ecosystem there is a community of organisms, but non-living components are absent.
E) The location of ecosystems around the world appears to be random. There is no relationship between ecosystem location and factors like climate.

Organisms that can produce their own food, such as plants through photosynthesis, form the base of the food chain in an ecosystem. This is because they are able to convert energy from the sun into usable energy for other organisms.

Note: A is false, as chemicals are cycled through ecosystems (e.g. water, carbon, nitrogen cycles). B is partially true, as energy does cycle through ecosystems, but it does not continually cycle as energy is lost as heat with each transfer (second law of thermodynamics). D is false, as non-living components such as water, air, and soil are crucial components of ecosystems. E is false, as ecosystem location is highly dependent on factors like climate, topography, and geological history.