The correct answer is A. Soil system.
The biotic component of the environment is made up of all living things. This includes plants, animals, and microorganisms. Soil is not a living thing, so it is not part of the biotic component of the environment.
Soil is a mixture of minerals, organic matter, water, and air. It is important for plant growth because it provides nutrients and holds water. Soil also supports a variety of organisms, including bacteria, fungi, and insects.
Plants are living things that make their own food through photosynthesis. They are an important part of the biotic component of the environment because they provide food and oxygen for other organisms. Plants also help to regulate the climate and prevent soil erosion.
Animals are living things that cannot make their own food. They must eat plants or other animals to survive. Animals are an important part of the biotic component of the environment because they help to control the population of plants and other animals. Animals also help to spread seeds and pollinate plants.
Microorganisms are tiny living things that can be found in soil, water, and air. They are an important part of the biotic component of the environment because they help to decompose dead plants and animals, recycle nutrients, and produce antibiotics.