Assertion: `[Fe(EDTA)]^(-)` complex is octahedral in shape.
Reason: EDTA is a hexadentate ligand and undergoing `sp^(3)d^(2)` hybridisation.

Options

A. If assertion is true but the reason is false
B. If assertion is false but reason is true
C. If both assertion and reason are true and the reason is the correct explanation of assertion
D. If both assertion and reason are true but reason is not the correct explanation of assertion

Explanation

To solve the given question, we need to analyze both the assertion and the reason provided regarding the `[Fe(EDTA)]^(-)` complex.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that the `[Fe(EDTA)]^(-)` complex is octahedral in shape.
- EDTA (Ethylenediaminetetraacetic acid) is a hexadentate ligand, meaning it can coordinate to a metal ion through six donor atoms (four carboxylate oxygen atoms and two amine nitrogen atoms).
- When a hexadentate ligand like EDTA coordinates to a metal ion such as Fe, it occupies six coordination sites around the metal, leading to an octahedral geometry.

**Conclusion**: The assertion is correct.

2. **Understanding the Reason**:
- The reason states that EDTA is a hexadentate ligand and undergoes `sp^(3)d^(2)` hybridization.
- While it is true that EDTA is a hexadentate ligand, the hybridization mentioned is incorrect.
- In the case of strong field ligands like EDTA, the hybridization that occurs is actually `d^(2)sp^(3)`, not `sp^(3)d^(2)`. This is because the d-orbitals are involved in the hybridization process to accommodate the strong field effect and pairing of electrons.

**Conclusion**: The reason is incorrect.

3. **Final Evaluation**:
- Since the assertion is correct and the reason is incorrect, we conclude that the statement is partially true. The `[Fe(EDTA)]^(-)` complex is indeed octahedral, but the hybridization described in the reason is not accurate.

### Summary:
- **Assertion**: Correct
- **Reason**: Incorrect