The amount of oxidixze orgnic substance present in water is called

Options

A. DO
B. COD
C. BOD
D. TLV

Answer

To answer the question, "The amount of oxidized organic substance present in water is called," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Terms**:
- We need to identify the relevant terms related to organic substances in water. The key terms mentioned are DO (Dissolved Oxygen), COD (Chemical Oxygen Demand), BOD (Biological Oxygen Demand), and TLV (Threshold Limiting Value).

2. **Identifying the Correct Term**:
- **DO (Dissolved Oxygen)**: This refers to the amount of oxygen dissolved in water, not specifically related to organic substances.
- **BOD (Biological Oxygen Demand)**: This measures the amount of oxygen required by bacteria to decompose organic matter in water, but it does not directly measure oxidized substances.
- **COD (Chemical Oxygen Demand)**: This measures the total amount of oxygen required to chemically oxidize organic and inorganic substances in water, making it the most relevant term for oxidized organic substances.
- **TLV (Threshold Limiting Value)**: This refers to the maximum allowable concentration of a substance in water, which is not directly related to the measurement of oxidized organic substances.

3. **Conclusion**:
- The term that specifically refers to the amount of oxidized organic substance present in water is **COD (Chemical Oxygen Demand)**.

### Final Answer:
The amount of oxidized organic substance present in water is called **Chemical Oxygen Demand (COD)**.

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