**Question:** Process of mixing waste with cement before disposal is known as -

A. Incineration
B. Composting
C. Landfilling
D. Wastewater treatment

**Correct Answer: C. Landfilling**

**Core Concept:**
Landfilling is a waste management method where waste is disposed of in a designated area, typically a landform known as a "landfill." This process involves the disposal of solid waste materials directly into a sanitary landfill, where it is covered with layers of soil and compacted to prevent leachate production and الروائح.

**Why the Correct Answer is Right:**
Landfilling is the right answer because it specifically describes the process of mixing waste with cement before disposal. This practice is aimed at preventing leachate production, which is a liquid byproduct of waste decomposition that may contain harmful substances and contaminants. By mixing waste with cement, the leachate formation is reduced, and the waste becomes more stable, decreasing the risk of environmental pollution and potential health hazards.

**Why Each Wrong Option is Incorrect:**

A. Incineration (Option A) involves burning waste to reduce its volume and generate energy. Incineration is not the correct answer because it does not involve mixing waste with cement before disposal, rather it deals with the burning of waste.

B. Composting (Option B) is a waste management method that involves the decomposition of organic waste into compost, which is a natural fertilizer. Composting does not involve mixing waste with cement before disposal.

D. Wastewater treatment (Option D) is the process of removing contaminants from wastewater to protect the environment and public health. This process is distinct from landfilling as it focuses on treating liquid waste rather than solid waste.

**Clinical Pearl:**

While landfilling is one of the waste management methods, it is essential to consider other waste management strategies as well. Integrating waste segregation, recycling, and composting can significantly contribute to a more sustainable and effective waste management approach. By reducing waste generation, recycling, and utilizing composting, we can minimize the need for landfilling, ultimately leading to a cleaner environment and improved public health.