Which among the following is not an application of dissolved gases in water?

Options

A. Tastes of water
B. Photosynthesis of aquatic plants
C. Salinity of sea water
D. respiration of aquatic organisms

Explanation

To solve the question "Which among the following is not an application of dissolved gases in water?", we will analyze each option provided.

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify which option does not relate to the applications of dissolved gases in water.

2. **Review the Options**:
- **Option 1**: Taste of water
- **Option 2**: Photosynthesis of aquatic plants
- **Option 3**: Salinity of seawater
- **Option 4**: Respiration of aquatic organisms

3. **Analyze Each Option**:
- **Option 1: Taste of water**: The taste of water is influenced by dissolved gases like oxygen (O2) and carbon dioxide (CO2), which contribute to the freshness of water. This is an application of dissolved gases.
- **Option 2: Photosynthesis of aquatic plants**: Aquatic plants require CO2 for photosynthesis, which is dissolved in water. This is also an application of dissolved gases.
- **Option 3: Salinity of seawater**: Salinity refers to the concentration of dissolved salts in water, not gases. Therefore, this is not an application of dissolved gases.
- **Option 4: Respiration of aquatic organisms**: Aquatic organisms require dissolved oxygen (O2) for respiration. This is an application of dissolved gases.

4. **Identify the Correct Answer**: Based on the analysis, Option 3 (Salinity of seawater) is the only option that does not relate to the application of dissolved gases in water.

### Final Answer:
The correct answer is **Option 3: Salinity of seawater**.

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