Assertion : A triangle is a polygon.
Reason : A polygon is a closed figure with more than three sides.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion.
B. If both assertion and reason are true but reason is not the correct explanation of assertion.
C. If assertion is true but reason is false.
D. If assertion is false but reason is true

Answer

To solve the question, we need to analyze the assertion and the reason provided:

**Assertion:** A triangle is a polygon.
**Reason:** A polygon is a closed figure with more than three sides.

### Step-by-Step Solution:

1. **Understanding the Assertion:**
- A triangle is defined as a closed figure with three sides.
- By definition, a polygon is any closed figure made up of line segments (sides).
- Since a triangle has three sides and is a closed figure, it fits the definition of a polygon.
- Therefore, the assertion "A triangle is a polygon" is **True**.

2. **Understanding the Reason:**
- The reason states that "A polygon is a closed figure with more than three sides."
- This statement is incorrect because polygons can have three or more sides.
- For example, a triangle (3 sides) and a quadrilateral (4 sides) are both polygons.
- Hence, the reason "A polygon is a closed figure with more than three sides" is **False**.

3. **Evaluating the Options:**
- Now we need to determine the relationship between the assertion and the reason.
- The options are:
1. If both assertion and reason are true, reason is the correct explanation of assertion.
2. If both assertion and reason are true, but reason is not the correct explanation of assertion.
3. If assertion is true but reason is false.
4. If both assertion and reason are false.

- Since we have established that the assertion is true and the reason is false, the correct option is:
- **Option 3: If assertion is true but reason is false.**

### Final Answer:
The correct option is **Option 3**: Assertion is true but reason is false.

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