Which of the following exhibits the greatest number of oxidation states ?
(i) Zr (ii) Ti (iii) V (iv) Ni (v) Mn.

Explanation

To determine which of the given elements exhibits the greatest number of oxidation states, we will analyze each element one by one based on their electronic configurations and possible oxidation states.

### Step-by-Step Solution:

1. **Zirconium (Zr)**:
- Atomic number: 40
- Electronic configuration: [Kr] 5s² 4d²
- Valence electrons: 4 (2 from 5s and 2 from 4d)
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