The pair of the compounds in which both the metals are in the highest possible oxidation state is

Explanation

To solve the question, we need to determine the oxidation states of the metals in each of the given compounds and identify the pair where both metals are in their highest oxidation states.

### Step-by-Step Solution:

1. **Analyze the first option: MnO2 and FeCl3**
- For **MnO2**:
- Let the oxidation state of Mn be \( x \).
- The oxidation state of O is \(-2\).
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