Answer:
B. trees
Step-by-step explanation:
A biotic factor is something in an environment or ecosystem that is living. For example, plants and animals are biotic factors. An abiotic factor is just the opposite-they are not living. Rocks and water are examples of abiotic factors.
Soil composition, temperature and sunlight are all not alive. Therefore, they must be abiotic factors.
Trees are living organism. This means that they are biotic factors. So, the correct answer is B: trees.