The correct option is (a).
Explanation
Waste management relies on distinguishing between biodegradable materials, which can be broken down by biological processes, and non-biodegradable materials, which persist in the environment. The method of disposal or processing depends on this classification.
Statement 1 is Correct:
Plant and animal wastes are organic matter. They are biodegradable, meaning they can be broken down by microorganisms (bacteria and fungi) into simpler substances. This natural decomposition process converts organic waste into nutrient-rich manure (humus), which is beneficial for soil fertility.
Statement 2 is Incorrect:
The process of converting plant and animal waste into manure is technically called composting (or vermicomposting when earthworms are used). Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials at high temperatures, converting them into ash, flue gas, and heat. Incineration is not used to produce manure.
Statement 3 is Incorrect:
Plastics and glass are non-biodegradable materials. Their molecular structure resists breakdown by microorganisms. Consequently, they persist in the environment for hundreds to thousands of years. Organic waste decomposes much faster, typically within weeks or months depending on environmental conditions.
Key Takeaway:
Composting is the biological decomposition of organic waste into manure, while incineration is the thermal destruction of waste. Biodegradable waste decomposes rapidly compared to non-biodegradable materials like plastic and glass.