Which of the following is different from others ?

Options

A. Micron
B. Light year
C. Mole
D. Angstrom

Answer

To determine which of the following options is different from the others, we will analyze each option based on their definitions and classifications.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are micron, light year, mole, and angstrom.

2. **Define Each Option**:
- **Micron**: A micron (or micrometer) is a unit of length equal to 10^-6 meters. It is used to measure small distances.
- **Light Year**: A light year is the distance that light travels in one year. It is also a unit of distance.
- **Mole**: A mole is a unit that measures the amount of substance. It is one of the seven fundamental quantities in physics and chemistry.
- **Angstrom**: An angstrom is a unit of length equal to 10^-10 meters, commonly used to measure wavelengths, particularly in the field of atomic and molecular physics.

3. **Classify the Options**:
- Micron, light year, and angstrom are all units of distance.
- Mole is a unit of the amount of substance.

4. **Determine the Odd One Out**: Since micron, light year, and angstrom are all units of distance, while mole is a unit of amount of substance, mole is the different one.

5. **Conclusion**: The option that is different from the others is **mole**.

### Final Answer:
**Mole** is different from the others.

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