Arrange following complex ions in increasing order of crystal field splitting energy `(Delta_(0))`.

Explanation

To arrange the given complex ions in increasing order of crystal field splitting energy (Δ₀), we need to consider the nature of the ligands present in each complex. The strength of the ligands determines the extent of crystal field splitting, with strong field ligands causing greater splitting compared to weak field ligands.

### Step-by-step Solution:

1. **Identify the Ligands**:
- The ligands in the complexes are crucial for determining the crystal field splitting energy. Common ligands include CN⁻ (cyanide), NH₃ (ammonia), and H₂O (water).

2. **Refer to the Spectrochemical Series**:
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