A) By breaking down the remains of dead organisms.
B) By making their own food from the sun.
C) By going to the grocery store and shopping for food.

A) The amount of energy is highest at the top of the pyramid.
B) The amount of energy is highest in the middle of the pyramid.
C) The amount of energy is highest at the bottom of the pyramid.

A) The struggle among organisms to survive in a habitat with limited resources.
B) The way that animals mate with one another.
C) A term scientists use that shows that organisms are getting along in an environment.

A) Parasitism
B) Mutualism
C) Commensalism

A) An apple growing from a tree.
B) Feathers on a bird fluffing up in the wind.
C) Fungus on a beetle bug.

A) Helped
B) Harmed

A) Rapidly
B) Never
C) Slowly

A) Wildebeests don't eat grass so the zebras can have it all
B) Zebras don't eat grass so the wildebeests can have it all
C) Zebras eat tall grass and wildebeests eat short grass

A) Owl is predator
B) Rabbit is predator

A) Because the parasite should probably die on its own.
B) It wouldn't be a bad a idea for a parasite to kill its host.
C) Because the parasite depends on its host for its needs.

A) Comparison
B) Competition
C) No one would touch them
D) Everyone getting along