Assertion : A convex mirror is preferred over a plane mirror in vehicles to observer traffic coming from behind.
Reason : Images formed by convex mirrors are erect and diminished in size.

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

Explanation

To analyze the assertion and reason provided in the question, we can break down the solution into the following steps:

### Step 1: Understanding the Assertion
The assertion states that a convex mirror is preferred over a plane mirror in vehicles to observe traffic coming from behind.

### Step 2: Understanding the Reason
The reason provided is that images formed by convex mirrors are erect and diminished in size.

### Step 3: Characteristics of Convex Mirrors
- Convex mirrors always produce images that are virtual, erect, and diminished in size.
- This means that the images appear smaller than the actual object, allowing a wider field of view.

### Step 4: Characteristics of Plane Mirrors
- Plane mirrors also produce erect images, but they do not diminish the size of the image.
- The size of the image in a plane mirror is the same as the size of the object, which can limit the field of view.

### Step 5: Comparison of Field of View
- Since convex mirrors produce smaller images, they allow for a larger field of view with a smaller mirror size.
- In contrast, a plane mirror would need to be larger to provide a similar field of view, which is impractical for vehicles.

### Step 6: Conclusion
Both the assertion and reason are true. The reason correctly explains why convex mirrors are preferred in vehicles, as they provide a wider field of view with smaller, erect images.

### Final Answer
- **Assertion**: True
- **Reason**: True
- **Explanation**: The reason is the correct explanation of the assertion.

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