Match column I with column II and select the correct option from the given codes:
`{:("Column I","Column II"),(A" Nitrosomonas, Nitrococcus",(i)" Ammonia to Nitrite"),(B" Nitrobacter, Nitrocystis",(ii)" Nitrite to Nitrate"),(C" Pseudomonas",(iii)" Nitrate to "N_(2)):}`

Options

A. (a) A-(i), B-(ii), C-(iii)
B. (b) A-(i), B-(iii), C-(ii)
C. (c) A-(ii), B-(i), C-(iii)
D. (d) A-(ii), B-(iii), C-(i)

Answer

To solve the problem of matching the components in Column I with those in Column II, we will analyze each item in Column I and determine its corresponding match in Column II based on the biological processes involved.

### Step-by-Step Solution:

1. **Identify the first pair (A)**:
- **Column I (A)**: Nitrosomonas, Nitrococcus
- These bacteria are involved in the first step of nitrification, where ammonia (NH₃) is converted into nitrite (NO₂⁻).
- **Match**: (i) Ammonia to Nitrite

2. **Identify the second pair (B)**:
- **Column I (B)**: Nitrobacter, Nitrocystis
- These bacteria are responsible for the second step of nitrification, converting nitrite (NO₂⁻) into nitrate (NO₃⁻).
- **Match**: (ii) Nitrite to Nitrate

3. **Identify the third pair (C)**:
- **Column I (C)**: Pseudomonas
- This bacterium is involved in the process of denitrification, where nitrate (NO₃⁻) is converted back into nitrogen gas (N₂).
- **Match**: (iii) Nitrate to N₂

4. **Compile the matches**:
- A matches with (i)
- B matches with (ii)
- C matches with (iii)

5. **Final Matching**:
- A → (i) Ammonia to Nitrite
- B → (ii) Nitrite to Nitrate
- C → (iii) Nitrate to N₂

6. **Select the correct option**:
- The matches can be summarized as:
- A1 (Nitrosomonas, Nitrococcus → Ammonia to Nitrite)
- B2 (Nitrobacter, Nitrocystis → Nitrite to Nitrate)
- C3 (Pseudomonas → Nitrate to N₂)
- The correct option is A1, B2, C3, which corresponds to option A.

### Final Answer:
Hence, the correct answer is option A: A1, B2, C3.