The correct answer is option 3: organic biofertilizer. Vermicompost is a type of fertilizer that is produced through the process of vermicomposting. Vermicomposting is the breakdown of organic matter, such as food scraps and plant waste, by earthworms and other microorganisms.
Option 1, inorganic fertilizer, is incorrect because vermicompost is an organic fertilizer, meaning it is derived from natural sources rather than synthetic chemicals.
Option 2, toxic substance, is incorrect because vermicompost is not toxic. In fact, it is considered a safe and environmentally friendly option for fertilizing plants.
Option 4, synthetic fertilizer, is incorrect because vermicompost is not a synthetic fertilizer. Synthetic fertilizers are chemically manufactured and do not contain organic matter like vermicompost does.
Vermicompost is rich in essential nutrients, microbial activity, and organic matter, making it a valuable soil amendment. It improves soil structure, enhances nutrient availability, and promotes healthy plant growth.