Consider the following aqueous solutions and assume 100% ionisation in electrolytes :
I. `0.1 m` urea
II. `0.04 m Al_(2)(SO_(4))_(3)`
III. `0.0.5 m CaCl_(2)`
IV. `0.005m NaCl`
The correct statement regarding the above solutions is :

Options

A. freezing point will be lowest for solution I
B. freezing point will be highest for solution IV
C. boiling point will be highest for solution IV
D. vapour pressure will be highest for solution II

Explanation

To solve the problem, we need to analyze the given solutions based on their molality and the number of particles they produce upon dissociation. We will calculate the effective concentration (i.e., the van 't Hoff factor \(i\)) for each solution, which is crucial for determining the colligative properties such as freezing point depression.

### Step-by-Step Solution:

1. **Identify the nature of each solute:**
- **Urea**: A non-electrolyte that does not dissociate in solution.
- **Aluminum sulfate \((Al_2(SO_4)_3)\)**: An electrolyte that dissociates into 2 Al\(^{3+}\) ions and 3 SO\(_4^{2-}\) ions.
- **Calcium chloride \((CaCl_2)\)**: An electrolyte that dissociates into 1 Ca\(^{2+}\) ion and 2 Cl\(^{-}\) ions.
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