Question

which of the following best illustrates an interaction between two biotic factors in an environment that can have an affect on population sizes?
a plants use sunlight and water to grow.
b a family of rabbits living in the ground.
c water carries rocks downstream.
d cows eating grass in a field.

Explanation:

Biotic factors are living components of an ecosystem. Cows (biotic) and grass (biotic) show an interaction where cows (herbivores) consume grass (producer). In option A, sunlight is abiotic. In option B, it's just a description of a rabbit's habitat (no interaction between two biotic factors in a consumptive or mutually - beneficial etc. sense). In option C, water is abiotic.

Answer:

D. Cows eating grass in a field.