Given below are two statements : One is labelled as Assertion A and the other labelled as Reason R.
Assertion A : Lithium halides are some what covalent in nature.
Reason R : Lithium possess high polarisation capability.
In the light of the above statements, choose the most appropriate answer from the options given below :

Options

A. A is true but R is false
B. A is false but R is true
C. Both A and R are true but R is NOT the correct explanation of A
D. Both A and R are true but R is the correct explanation of A

Answer

To solve the question regarding the Assertion A and Reason R, we will analyze both statements step by step.

### Step 1: Analyze Assertion A
**Assertion A** states: "Lithium halides are somewhat covalent in nature."

- Lithium halides, such as LiCl, LiBr, and LiI, do exhibit some covalent character. This is due to the small size of the lithium ion (Li⁺), which leads to a significant polarizing effect on the electron cloud of the halide ions (Cl⁻, Br⁻, I⁻).

### Step 2: Analyze Reason R
**Reason R** states: "Lithium possesses high polarization capability."

- Lithium does indeed have a high polarizing power because it is a small cation. According to Fajans' rules, the smaller the cation, the greater its ability to distort the electron cloud of the anion, which increases covalent character in the bond formed.

### Step 3: Establish the Relationship
Now we need to determine if Reason R correctly explains Assertion A.

- Since lithium's high polarizing power contributes to the covalent character of lithium halides, Reason R does provide a correct explanation for Assertion A.

### Conclusion
Both Assertion A and Reason R are true, and Reason R is the correct explanation for Assertion A.

### Final Answer
The correct option is **1**: Assertion is true and Reason is true, and Reason is the correct explanation for Assertion.

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