`1 mum` is

Options

A. `10^(-6)m`
B. `10^(-9)m`
C. `10^(-10)m`
D. `10^(-3)m`

Explanation

**Step-by-Step Solution:**

1. **Understanding the Unit "Micrometer":**
- The term "micrometer" is a unit of measurement that is often used to express very small lengths. It is commonly used in biology to measure the size of cells and microorganisms.

2. **Breaking Down the Prefix "Micro":**
- The prefix "micro" in the metric system represents a factor of \(10^{-6}\). This means that one micrometer is one-millionth of a meter.

3. **Converting Micrometers to Meters:**
- To express 1 micrometer in meters, we can use the relationship defined by the prefix:
\[ 1 \text{ micrometer} = 1 \text{ micro} \times 1 \text{ meter} = 10^{-6} \text{ meters} \]

4. **Conclusion:**
- Therefore, the final answer is:
\[ 1 \text{ micrometer} = 10^{-6} \text{ meters} \]

5. **Identifying the Correct Option:**
- If options are provided, the correct option that represents 1 micrometer would be \(10^{-6} \text{ meters}\).