BOD of waste water is estimated by measuring the amount of

Options

A. total organic matter
B. biodegradable organic matter
C. oxygen evolution
D. oxygen consumption

Explanation

To answer the question regarding how the Biochemical Oxygen Demand (BOD) of wastewater is estimated, we can follow these steps:

### Step-by-Step Solution:

1. **Understand BOD**: BOD stands for Biochemical Oxygen Demand. It is a measure of the amount of dissolved oxygen needed by aerobic microorganisms to decompose organic matter in water.

2. **Identify What is Measured**: To estimate BOD, we need to measure the amount of oxygen consumed by microorganisms during the decomposition process of organic matter in the wastewater.

3. **Analyze the Options**:
- **Total Organic Matter**: This refers to all organic materials present but does not directly measure oxygen consumption.
- **Biodegradable Organic Matter**: While this is relevant, it still does not measure oxygen consumption directly.
- **Oxygen Evolution**: This refers to the production of oxygen, which is not what we are measuring for BOD.
- **Oxygen Consumption**: This option directly relates to the amount of oxygen consumed by microorganisms, which is what BOD measures.

4. **Conclusion**: The correct answer to the question is that BOD of wastewater is estimated by measuring the amount of **Oxygen Consumption**.

### Final Answer:
BOD of wastewater is estimated by measuring the amount of **Oxygen Consumption**.

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