Water pollution is best assessed by determining

Options

A. DO
B. BOD and turbidity
C. DO and acidity
D. Hardness and alkalinity

Answer

To determine the best assessment of water pollution, we can follow these steps:

### Step 1: Understand the Concept of Water Pollution
Water pollution refers to the contamination of water bodies (like rivers, lakes, and oceans) due to harmful substances or pollutants. It is essential to measure the extent of this pollution to manage and mitigate its effects.

**Hint:** Consider what factors indicate the presence of pollutants in water.

### Step 2: Identify Key Indicators of Water Quality
There are several indicators used to assess water quality, including:
- **Biochemical Oxygen Demand (BOD)**: This measures the amount of oxygen consumed by bacteria while decomposing organic matter in water.
- **Turbidity**: This measures the clarity of water and indicates the presence of suspended particles.

**Hint:** Think about how each indicator reflects the health of the water body.

### Step 3: Analyze the Role of BOD
BOD is a critical measure because:
- An increase in BOD indicates a higher level of organic matter in the water.
- More organic matter leads to an increase in bacteria, which consume oxygen for decomposition.
- A high BOD level suggests that the water is polluted and may not support aquatic life.

**Hint:** Reflect on how the decomposition process affects oxygen levels in water.

### Step 4: Analyze the Role of Turbidity
Turbidity is also an important measure because:
- It indicates the clarity of water; higher turbidity means more suspended particles.
- Increased turbidity can be a sign of pollution from sediments, algae, or other contaminants.
- It can affect aquatic life by reducing light penetration and harming organisms that rely on clear water.

**Hint:** Consider how visibility in water relates to the presence of pollutants.

### Step 5: Conclusion
Based on the analysis, the best assessment of water pollution is determined by measuring both BOD and turbidity. These two indicators provide a comprehensive view of the water quality and the extent of pollution.

**Final Answer:** Water pollution is best assessed by determining **BOD and turbidity**.

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