Question

what are biodegradable substances?
○ a. materials that can be decomposed by living organisms
○ b. organic waste that is incinerated
○ c. plastic products that last indefinitely
○ d. waste that cannot be reused

which waste management practice helps improve soil health?
○ a. landfilling
○ b. discarding waste in open areas
○ c. incineration
○ d. composting

Explanation:

First Question (What are biodegradable substances?):

To determine the correct answer, we analyze each option:

• Option a: Biodegradable substances are defined as materials that can be broken down (decomposed) by living organisms (like bacteria, fungi). This matches the definition.
• Option b: Incineration is burning waste, not related to biodegradation. So this is incorrect.
• Option c: Plastic products that last indefinitely are non - biodegradable (like most plastics), so this is wrong.
• Option d: Biodegradable waste can often be reused or recycled, and the definition of biodegradable has nothing to do with reusability. So this is incorrect.

We analyze each waste management practice:

• Option a: Landfilling involves burying waste. It does not improve soil health; in fact, it can contaminate soil.
• Option b: Discarding waste in open areas leads to pollution and does not improve soil health.
• Option c: Incineration is burning waste, which has no direct positive impact on soil health.
• Option d: Composting is the process of decomposing organic waste into a nutrient - rich material (compost) that can be added to soil to improve its fertility, structure, and water - holding capacity.

Answer:

a. Materials that can be decomposed by living organisms

Second Question (Which waste management practice helps improve soil health?):