If the solubility of three nitrogenous wastes is arranged in the ascending order `S_1 lt S_2 lt S_3` and their toxicity levels also arranged in ascending order `T_1 lt T_2 lt T_3` identify the correct option.
`{:(,"Ammonia","Urea","Uric acid"),(i,S_3T_1,S_2T_3,S_1T_2),(ii,S_2T_2,S_1T_1,S_3T_3),(iii,S_1T_3,S_2T_2,S_3T_3),(iv,S_3T_3,S_2T_2,S_1T_1):}`

Options

A. i
B. ii
C. iii
D. iv

Answer

To solve the question, we need to analyze the solubility and toxicity of three nitrogenous wastes: ammonia, urea, and uric acid. We will arrange them in ascending order based on their solubility and toxicity levels.

### Step-by-Step Solution:

1. **Identify the Nitrogenous Wastes**:
- The three nitrogenous wastes are:
- Ammonia
- Urea
- Uric acid

2. **Determine Solubility (S)**:
- **Ammonia**: Highly soluble in water (S3)
- **Urea**: Moderately soluble in water (S2)
- **Uric Acid**: Least soluble in water (S1)

Therefore, the order of solubility is:
\[ S_1 \text{ (Uric Acid)} < S_2 \text{ (Urea)} < S_3 \text{ (Ammonia)} \]

3. **Determine Toxicity (T)**:
- **Ammonia**: Highly toxic (T3)
- **Urea**: Moderately toxic (T2)
- **Uric Acid**: Least toxic (T1)

Therefore, the order of toxicity is:
\[ T_1 \text{ (Uric Acid)} < T_2 \text{ (Urea)} < T_3 \text{ (Ammonia)} \]

4. **Combine the Results**:
- From the above analysis, we can summarize:
- Uric Acid: \( S_1, T_1 \)
- Urea: \( S_2, T_2 \)
- Ammonia: \( S_3, T_3 \)

5. **Match with Options**:
- Now we check the options given in the question:
- (i) \( S_3T_1, S_2T_3, S_1T_2 \)
- (ii) \( S_2T_2, S_1T_1, S_3T_3 \)
- (iii) \( S_1T_3, S_2T_2, S_3T_3 \)
- (iv) \( S_3T_3, S_2T_2, S_1T_1 \)

The correct arrangement based on our findings is:
- Ammonia: \( S_3T_3 \)
- Urea: \( S_2T_2 \)
- Uric Acid: \( S_1T_1 \)

This matches option (iv):
\[ S_3T_3, S_2T_2, S_1T_1 \]

### Final Answer:
The correct option is **(iv) \( S_3T_3, S_2T_2, S_1T_1 \)**.

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