Question

which list includes only biotic parts of an ecosystem?
a. decomposers, soil, nutrients
b. mammals, birds, oxygen
c. algae, grasses, animals
d. soil, water, air

Explanation:

Biotic parts are living components. Algae, grasses, and animals are living organisms. Decomposers are biotic but soil and nutrients are abiotic. Mammals and birds are biotic but oxygen is abiotic. Soil, water, and air are abiotic.

Answer:

C. Algae, grasses, animals