Assertion : Water is specially effective in screening the electrostatic interactions between the dissolved ions.
Reason : The force of ionic interactions depends upon the dielectric constant (`epsi`) of the solvent .

Options

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

Explanation

To solve the question, we need to analyze the assertion and reason statements provided:

### Step 1: Understand the Assertion
The assertion states that "Water is especially effective in screening the electrostatic interactions between the dissolved ions." This means that water can reduce the strength of the electrostatic forces between ions when they are dissolved in it.

### Step 2: Understand the Reason
The reason states that "The force of ionic interactions depends upon the dielectric constant (ε) of the solvent." The dielectric constant is a measure of a solvent's ability to reduce the electrostatic forces between charged particles. A higher dielectric constant indicates a greater ability to screen these forces.

### Step 3: Relate the Assertion to the Reason
Water has a high dielectric constant, which means it is very effective at reducing the electrostatic interactions between ions. When ionic compounds like NaCl dissolve in water, the water molecules surround the ions and weaken the ionic bonds due to their high dielectric constant.

### Step 4: Conclusion
Both the assertion and the reason are true. The assertion is correct because water effectively screens electrostatic interactions, and the reason is correct because the ability of a solvent to screen these interactions is indeed related to its dielectric constant.

### Final Answer
Both the assertion and reason are true, and the reason correctly explains the assertion.

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