The conjugate base of `OH^(-)` is :

Options

A. `O_(2)`
B. `H_(2)O`
C. `O^(-)`
D. `O^(2-)`

Explanation

To find the conjugate base of the hydroxide ion (OH⁻), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Conjugate Bases**:
- According to the Bronsted-Lowry theory, a conjugate base is formed when an acid donates a proton (H⁺). Therefore, to find the conjugate base of a given species, we need to remove a proton from it.

2. **Identify the Species**:
- In this case, we are looking for the conjugate base of the hydroxide ion (OH⁻).

3. **Remove a Proton (H⁺)**:
- To find the conjugate base, we subtract H⁺ from OH⁻:
\[ \text{Conjugate base} = \text{OH}^- - \text{H}^+ \]

4. **Perform the Calculation**:
- When we remove H⁺ from OH⁻, we are left with:
\[ \text{OH}^- - \text{H}^+ = \text{O}^{2-} \]

5. **Conclusion**:
- The conjugate base of OH⁻ is O²⁻.

### Final Answer:
The conjugate base of OH⁻ is O²⁻.

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