Correct Option: C. Competition among species Explanation of the Correct Answer In ecology, biotic factors refer to the living components of an ecosystem that can affect the organisms within it. These include interactions between organisms, such as predation, competition, symbiosis, and disease. Competition among species is a prime example of a biotic factor. It occurs when two or more species vie for the same resources, such as food, space, or mates. This competition can influence population dynamics, community structure, and the overall health of an ecosystem. For instance, if one species is more efficient at obtaining resources, it may outcompete another species, leading to a decline in the latter's population. This interaction can shape the biodiversity and stability of the ecosystem. Why the Other Options Are Incorrect A. Temperature - Explanation: Temperature is an abiotic factor, meaning it is a non-living component of the environment. It affects the metabolic rates of organisms, the distribution of species, and the overall functioning of ecosystems. While temperature can influence biotic interactions (like competition), it is not a living factor itself. B. Soil pH - Explanation: Soil pH is also an abiotic factor. It affects nutrient availability and the types of plants that can thrive in a given area. While soil pH can influence the types of organisms that can live in an ecosystem, it does not involve interactions between living organisms. D. Light intensity - Explanation: Light intensity is another abiotic factor. It plays a crucial role in photosynthesis, affecting plant growth and, consequently, the entire food web. Like temperature and soil pH, light intensity influences living organisms but is not a living factor itself. Summary of Key Points

• Biotic factors are living components of an ecosystem, such as competition, predation, and symbiosis.
• Competition among species is a significant biotic factor that can shape population dynamics and community structure.
• Abiotic factors (like temperature, soil pH, and light intensity) are non-living elements that influence ecosystems but do not involve interactions between living organisms.
• Understanding the distinction between biotic and abiotic factors is crucial for studying ecology and environmental science.

Revision Summary

• Biotic factors include interactions among living organisms, such as competition.
• Competition can affect species populations and ecosystem dynamics.
• Abiotic factors (temperature, soil pH, light intensity) are non-living and influence ecosystems but do not involve living interactions.
• Recognizing the difference between biotic and abiotic factors is essential for understanding ecological relationships.