Out of following solutions, the one having the highest boiling point will be:

Options

A. 0.1 M NaCl
B. `0.1 M BaCl_(2)`
C. `0.1 M KNO_(3)`
D. `0.1 M K_(4)[Fe(CN)_(6)]`

Explanation

To determine which solution has the highest boiling point, we will use the concept of boiling point elevation, which is influenced by the van 't Hoff factor (i). The van 't Hoff factor represents the number of particles (ions or molecules) a solute dissociates into when dissolved in a solvent. The more particles there are, the higher the boiling point elevation.

### Step-by-Step Solution:

1. **Identify the Solutions**: We have the following solutions to analyze:
- NaCl
- BaCl2
- KNO3
- K4[Fe(CN)6]

2. **Dissociation of NaCl**:
- NaCl dissociates into:
\[ \text{NaCl} \rightarrow \text{Na}^+ + \text{Cl}^- \]
- Number of ions (i) = 2

3. **Dissociation of BaCl2**:
- BaCl2 dissociates into:
\[ \text{BaCl}_2 \rightarrow \text{Ba}^{2+} + 2\text{Cl}^- \]
- Number of ions (i) = 3

4. **Dissociation of KNO3**:
- KNO3 dissociates into:
\[ \text{KNO}_3 \rightarrow \text{K}^+ + \text{NO}_3^- \]
- Number of ions (i) = 2

5. **Dissociation of K4[Fe(CN)6]**:
- K4[Fe(CN)6] dissociates into:
\[ \text{K}_4[\text{Fe(CN)}_6] \rightarrow 4\text{K}^+ + \text{Fe(CN)}_6^{4-} \]
- Number of ions (i) = 5

6. **Comparison of van 't Hoff Factors**:
- NaCl: i = 2
- BaCl2: i = 3
- KNO3: i = 2
- K4[Fe(CN)6]: i = 5

7. **Conclusion**:
- The solution with the highest van 't Hoff factor is K4[Fe(CN)6] with i = 5. Therefore, it will have the highest boiling point.

### Final Answer:
The solution with the highest boiling point is **K4[Fe(CN)6]**.