Abiotic limiting factors are nonliving influences on population growth. Which of the following is an abiotic limiting factor?

• A. Predation
• B. Temperature
• C. Water
• D. Sunlight

Answer: (D)

Abiotic limiting factors are nonliving influences that restrict population growth. Sunlight is a prime example because it provides the energy plants need to photosynthesize. When light is scarce, plant growth slows and primary production drops, which means less food for herbivores and, in turn, for the rest of the ecosystem. Predation is a living interaction, so it’s a biotic factor. Temperature and water are also nonliving, but sunlight specifically constrains the energy input that drives the whole food web, making it the clearest abiotic limiting factor in this context.