Natural aging of a lake by biological enrichment of its water called :-

Options

A. Biomagnification
B. Eutrophication
C. FOAM
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:** The question asks for the term that describes the natural aging of a lake due to biological enrichment of its water.

2. **Identifying the Options:** The options provided are:
- A) Biomagnification
- B) Eutrophication
- C) FOM (Friends of the Arcata Marsh)
- D) None of these

3. **Analyzing Biomagnification:**
- Biomagnification refers to the process where toxic substances accumulate in organisms at each successive level of the food chain. For example, substances like DDT or mercury become more concentrated as they move up the food chain.
- This process does not relate to the aging of a lake, so this option can be eliminated.

4. **Understanding Eutrophication:**
- Eutrophication is defined as the process by which a body of water becomes enriched in nutrients (like phosphorus and nitrogen), leading to increased growth of algae and other aquatic plants.
- This process can lead to decreased levels of dissolved oxygen in the water, which can harm aquatic life. It is essentially the natural aging process of a lake due to nutrient enrichment.

5. **Considering the Other Options:**
- FOM (Friends of the Arcata Marsh) is a project related to marshes and does not pertain to the aging of lakes.
- The option "None of these" can be disregarded since we have identified a suitable term.

6. **Conclusion:** Based on the analysis, the correct answer to the question is **Eutrophication**.

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