The conjugate base of ` (CH_3) NH_2^(o+)` is :

Options

A. `(CH_3)_3N`
B. `(CH_3)_2NH`
C. `(CH_3CH_2)_2NH_2`
D. `C_6H_5NHCH_2`

Explanation

To find the conjugate base of the compound \( (CH_3)NH_2^+ \), we need to understand what a conjugate base is. A conjugate base is formed when an acid donates a proton (H\(^+\)).

### Step-by-Step Solution:

1. **Identify the Acid**: The given compound is \( (CH_3)NH_2^+ \). This indicates that it is a protonated amine, meaning it has an extra hydrogen ion (H\(^+\)) attached to the nitrogen atom.

2. **Determine the Acidic Proton**: In this case, the acidic proton is the one attached to the nitrogen. When we refer to the conjugate base, we need to remove this acidic proton.

3. **Remove the Proton**: By removing the H\(^+\) from the nitrogen, we convert the protonated amine \( (CH_3)NH_2^+ \) into its corresponding base. The structure will change from \( (CH_3)NH_2^+ \) to \( (CH_3)NH_2 \).

4. **Write the Conjugate Base**: After removing the H\(^+\), we are left with \( (CH_3)NH_2 \), which is the conjugate base of \( (CH_3)NH_2^+ \).

5. **Conclusion**: Therefore, the conjugate base of \( (CH_3)NH_2^+ \) is \( (CH_3)NH_2 \).

### Final Answer:
The conjugate base of \( (CH_3)NH_2^+ \) is \( (CH_3)NH_2 \).