Biotic factors refer to:

• A. Non-living elements.
• B. Physical climate.
• C. Living organisms.
• D. Geological formations.

Answer: (C)

Biotic factors are the living parts of an environment—the plants, animals, fungi, bacteria, and the interactions among them. These living components shape ecosystems through feeding relationships, competition, symbiosis, and decomposition. Abiotic factors are the non-living conditions like climate (temperature, rainfall), light, soil properties, minerals, and geology. In this context, the description that refers to living organisms best represents biotic factors, while non-living elements such as climate or geological formations are abiotic.