Among the following complexes `(K-P)`
`K_(3)[Fe(CN)_(6)](K),[Co(Nh_(3))_(6)]CI_(3)(L)`
`Na_(3)[Co(oxalate)_(3)](M),[Ni(H_(2)O)_(6)]CI_(2)(N)`
`[Pt(CN)_(4)](O)` and `[Zn(H_(2)O)_(6)(NO_(3)_(2)(P)`
The diamagnetic are .

Options

A. `K,L,M,N`
B. `K,M,O,P`
C. `L,M,O,P`
D. `L,M,N,O`

Explanation

To determine which of the given complexes are diamagnetic, we need to analyze the electronic configurations of the central metal ions in each complex and count the number of unpaired electrons. A complex is diamagnetic if it has no unpaired electrons (n = 0).

### Step-by-Step Solution:

1. **Analyze K3[Fe(CN)6] (K)**:
- Central atom: Iron (Fe)
- Atomic number of Fe: 26
- Electronic configuration: 3d^6 4s^2
- Oxidation state in the complex: +3
- Electronic configuration in +3 state: 3d^5 4s^0
- CN is a strong field ligand, causing pairing of electrons.
- Configuration after pairing: 3d^5 (1 unpaired electron)
- **Result**: Paramagnetic (n = 1)

2. **Analyze [Co(NH3)6]Cl3 (L)**:
- Central atom: Cobalt (Co)
- Atomic number of Co: 27
- Electronic configuration: 3d^7 4s^2
- Oxidation state in the complex: +3
- Electronic configuration in +3 state: 3d^6 4s^0
- NH3 is a strong field ligand, causing pairing of electrons.
- Configuration after pairing: 3d^6 (0 unpaired electrons)
- **Result**: Diamagnetic (n = 0)

3. **Analyze Na3[Co(oxalate)3] (M)**:
- Central atom: Cobalt (Co)
- Oxidation state in the complex: +3
- Similar to the previous complex, Co is in +3 state: 3d^6 4s^0
- Oxalate is also a strong field ligand, causing pairing of electrons.
- Configuration after pairing: 3d^6 (0 unpaired electrons)
- **Result**: Diamagnetic (n = 0)

4. **Analyze [Ni(H2O)6]Cl2 (N)**:
- Central atom: Nickel (Ni)
- Atomic number of Ni: 28
- Electronic configuration: 3d^8 4s^2
- Oxidation state in the complex: +2
- Electronic configuration in +2 state: 3d^8 4s^0
- H2O is a weak field ligand, causing no pairing of electrons.
- Configuration: 3d^8 (2 unpaired electrons)
- **Result**: Paramagnetic (n = 2)

5. **Analyze [Pt(CN)4] (O)**:
- Central atom: Platinum (Pt)
- Atomic number of Pt: 78
- Electronic configuration: 5d^9 6s^1
- Oxidation state in the complex: +2
- Electronic configuration in +2 state: 5d^8 6s^0
- CN is a strong field ligand, causing pairing of electrons.
- Configuration after pairing: 5d^8 (0 unpaired electrons)
- **Result**: Diamagnetic (n = 0)

6. **Analyze [Zn(H2O)6](NO3)2 (P)**:
- Central atom: Zinc (Zn)
- Atomic number of Zn: 30
- Electronic configuration: 3d^10 4s^2
- Oxidation state in the complex: +2
- Electronic configuration in +2 state: 3d^10 4s^0
- Configuration: 3d^10 (0 unpaired electrons)
- **Result**: Diamagnetic (n = 0)

### Final Results:
The diamagnetic complexes among the given options are:
- [Co(NH3)6]Cl3 (L)
- Na3[Co(oxalate)3] (M)
- [Pt(CN)4] (O)
- [Zn(H2O)6](NO3)2 (P)