The standard unit of measuring an angle is ......... .

Options

A. cm
B. km
C. mm
D. degree

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the standard unit of measuring an angle.

2. **Identifying Options**: The options provided are:
- Option 1: Centimeter
- Option 2: Kilometer
- Option 3: Millimeter
- Option 4: Degree

3. **Analyzing the Options**:
- Centimeter, kilometer, and millimeter are units of length, not angle.
- The only option related to measuring angles is "degree".

4. **Understanding Angle Measurement**:
- Angles can be measured in degrees or radians.
- A complete circle is 360 degrees, and common angles are measured as 0°, 90°, 180°, 270°, and 360°.

5. **Conclusion**: The standard unit of measuring an angle is **degree**.

**Final Answer**: The standard unit of measuring an angle is **degree** (Option 4).

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