Assertion: Boron is metalloid.
Reason : Boron shows metallic nature.

Options

A. If both assertion and reason are true and the reason is the correct explanation of the assertion
B. If both assertion and reason are true but reason is nto the correct exaplation of the assertion
C. If assertion is true but reason is false
D. If the assertion and reason both are false

Explanation

To analyze the given assertion and reason, let's break it down step by step.

### Step 1: Understanding the Assertion
- **Assertion**: Boron is a metalloid.
- **Definition of Metalloid**: Metalloids are elements that have properties of both metals and non-metals. They are typically semiconductors and can exhibit characteristics of both categories.

### Step 2: Evaluating the Assertion
- Boron (B) is indeed classified as a metalloid. It has properties that are characteristic of both metals (such as conductivity) and non-metals (such as brittleness). Thus, the assertion is **true**.

### Step 3: Understanding the Reason
- **Reason**: Boron shows metallic nature.
- **Definition of Metallic Nature**: This refers to properties such as electrical conductivity, malleability, ductility, and luster, which are typically associated with metals.

### Step 4: Evaluating the Reason
- While boron does exhibit some metallic properties, it does not fully exhibit metallic nature in the same way that metals do. It is primarily a semiconductor and does not show all the characteristics of metals. Therefore, the reason is **false**.

### Step 5: Conclusion
- Since the assertion is true (Boron is a metalloid) and the reason is false (Boron does not fully show metallic nature), the correct conclusion is that the assertion is true but the reason is false.

### Final Answer
- The correct option is: Assertion is true but reason is false.

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