If BOD of sample water is very high, the sample is

Options

A. highly polluted
B. less polluted
C. not polluted
D. potable

Answer

**Step-by-Step Solution:**

1. **Understanding BOD**: BOD stands for Biological Oxygen Demand. It measures the amount of oxygen that microorganisms will consume while decomposing organic matter in water. A high BOD indicates a high level of organic pollution.

2. **Understanding DO**: DO stands for Dissolved Oxygen. It refers to the amount of oxygen that is available in water for aquatic organisms to breathe.

3. **Relationship Between BOD and DO**: BOD and DO are inversely proportional. This means that as BOD increases, the amount of dissolved oxygen (DO) decreases. Therefore, a high BOD indicates that there is less oxygen available in the water.

4. **Implications of High BOD**: When BOD is high, it suggests that there is a significant amount of organic matter in the water, which is being decomposed by microorganisms. This process consumes a lot of oxygen, leading to lower levels of dissolved oxygen.

5. **Conclusion**: If the BOD of a sample of water is very high, it indicates that the water is highly polluted. This is because the high level of organic matter and pollutants in the water leads to increased oxygen demand by microorganisms, resulting in lower dissolved oxygen levels.

**Final Answer**: If BOD of sample water is very high, the sample is highly polluted.

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