When an oxide of Mn
(A) is fused with KOH in the presence of an oxidizing agent and dissolved in water, it gives a dark solution of compound

Explanation

To solve the question, we need to determine the reaction that occurs when an oxide of manganese (Mn) is fused with potassium hydroxide (KOH) in the presence of an oxidizing agent, leading to the formation of a dark solution.

### Step-by-Step Solution:

1. **Identify the Oxide of Manganese**:
- The oxide of manganese that is commonly used in this reaction is manganese dioxide (MnO2).

**Hint**: Remember that manganese can exist in multiple oxidation states, and MnO2 is a common oxide.
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