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 regarding the solubility and toxicity levels of nitrogenous wastes (Ammonia, Urea, Uric Acid), we need to analyze the properties of each waste product.

### Step-by-Step Solution:

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

2. **Arrange by Solubility (S)**:
- **Ammonia**: Highly soluble in water.
- **Urea**: Moderately soluble in water.
- **Uric Acid**: Least soluble in water.

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

3. **Arrange by Toxicity (T)**:
- **Ammonia**: Highly toxic.
- **Urea**: Less toxic than ammonia.
- **Uric Acid**: Least toxic.

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

4. **Combine the Orders**: We now have:
- Solubility: \( S_1 < S_2 < S_3 \)
- Toxicity: \( T_1 < T_2 < T_3 \)

5. **Match the Options**: We need to find an option that correctly represents these orders.
- Looking at the options:
- (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 should reflect that:
- Ammonia (S3, T3) is the most soluble and most toxic.
- Urea (S2, T2) is in the middle.
- Uric Acid (S1, T1) is the least soluble and least toxic.

The correct option is:
\[ (iii) S_1T_3, S_2T_2, S_3T_1 \]

### Final Answer:
The correct option is (iii) \( S_1T_3, S_2T_2, S_3T_1 \).