In Arcata marshes, cleaning of wastewater involves :

Options

A. Utilization of microorganism only for pollution control
B. Filteration chlorination like chemical process
C. Removal of dissolved heavy metals through biological process
D. Only conventional method sewage treatment

Answer

To solve the question regarding the cleaning of wastewater in Arcata marshes, we will analyze each option provided and determine which one correctly describes the process involved.

### Step-by-Step Solution:

1. **Understanding the Context**: Arcata marshes are known for their natural wastewater treatment processes, which utilize various biological methods to clean water.

2. **Analyzing Option 1**:
- **Option**: Utilization of microorganisms only for pollution control.
- **Analysis**: This option suggests that only microorganisms are used for pollution control. However, this is incorrect because while microorganisms play a significant role, they are not the only method used in wastewater treatment. Therefore, this option is **not correct**.

3. **Analyzing Option 2**:
- **Option**: Filtration, Chlorine like chemical process.
- **Analysis**: This option implies that chemical processes such as filtration and chlorination are the primary methods used. While these methods can be part of wastewater treatment, they do not represent the primary method used in Arcata marshes, which focuses more on biological processes. Hence, this option is **not correct**.

4. **Analyzing Option 3**:
- **Option**: Removal of dissolved heavy metals through biological process.
- **Analysis**: This option indicates that biological processes are used to remove heavy metals from wastewater. This is accurate, as Arcata marshes utilize various biological methods, including the use of specific plants and microorganisms, to effectively remove heavy metals and other pollutants. Therefore, this option is **correct**.

5. **Analyzing Option 4**:
- **Option**: Only conventional method of serious treatment.
- **Analysis**: This option suggests that the method used is solely conventional. However, the treatment in Arcata marshes is not limited to conventional methods; it includes innovative biological approaches. Thus, this option is **not correct**.

### Conclusion:
Based on the analysis above, the correct answer is **Option 3: Removal of dissolved heavy metals through biological process**.

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