Which of the following is NOT a polygon ?

Options

A.
B.
C.
D.

Answer

To determine which of the given figures is NOT a polygon, we need to understand the definition of a polygon. A polygon is a closed figure made up of straight line segments. Let's analyze the options step by step.

### Step-by-Step Solution:

1. **Identify the Definition of a Polygon**:
- A polygon must have straight sides.
- A polygon must be a closed figure.

2. **Examine Each Option**:
- **Option 1**: Check if the figure consists of straight lines and is closed.
- If it meets both criteria, it is a polygon.
- **Option 2**: Check if the figure consists of straight lines and is closed.
- If it meets both criteria, it is a polygon.
- **Option 3**: Check if the figure consists of straight lines and is closed.
- If it has any curved lines or does not close properly, it is NOT a polygon.
- **Option 4**: Check if the figure consists of straight lines and is closed.
- If it meets both criteria, it is a polygon.

3. **Conclusion**:
- After examining all options, we find that **Option 3** contains a circle or curved line, which means it does not consist entirely of straight lines. Therefore, it does not meet the criteria for being a polygon.

### Final Answer:
**Option 3 is NOT a polygon.**

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