The abiotic factor that affect the population growth of an organism is

Step 1: Analyze the question The question asks for the abiotic factor that affects population growth. "Abiotic" means non-living, so we are looking for a physical or chemical component of the environment, not a living organism or something caused by one.

Step 2: Explain the concept Ecological factors fall into two groups:

• Biotic factors are living things and their interactions, such as predation, competition, parasitism, disease and food supply.
• Abiotic factors are non-living, such as rainfall, temperature, light, humidity, soil pH, wind and salinity.

Step 3: Examine each option

• A. Predator: A living organism, so it is biotic.
• B. Rainfall: A non-living climatic factor, so it is abiotic.
• C. Food shortage: Food comes from living organisms (plants or prey), so it is biotic.
• D. Disease: Caused by living pathogens such as bacteria, viruses and fungi, so it is biotic.

Step 4: Answer Only rainfall is non-living. It affects population growth by influencing water availability, plant growth (and so food supply) and breeding cycles. For example, locust and mosquito populations often rise sharply in the rainy season.

Tip: When you see "abiotic", ask yourself, "Is it alive, or caused by something alive?" If yes, cross it out. Abiotic factors are usually things you can find in a weather report or soil test: rain, temperature, light, wind and pH.