Which of the following is a non-metal ?

Options

A. Gallium
B. Indium
C. Boron
D. Aluminium

Explanation

To determine which of the given options is a non-metal, we can follow these steps:

### Step 1: Identify the Elements
The options provided are:
- Boron (B)
- Aluminum (Al)
- Gallium (Ga)
- Indium (In)

### Step 2: Classify Each Element
Now, we will classify each of these elements based on their position in the periodic table and their properties:
- **Boron (B)**: Located in group 13, boron is known as a metalloid but is often considered a non-metal due to its properties.
- **Aluminum (Al)**: Also in group 13, aluminum is a metal.
- **Gallium (Ga)**: Found in group 13 as well, gallium is a metal.
- **Indium (In)**: This element is also a metal and is located in group 13.

### Step 3: Conclusion
Among the options given, boron is the only element that is classified as a non-metal (or metalloid), while aluminum, gallium, and indium are all metals.

### Final Answer
**Boron (B) is the non-metal among the given options.**

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