Assertion `:` The mirrorrs used in search lights are parabolic and not concave spherical.
Reason `:` In a concave spherical mirrorr the image formed is always virtual.

Options

A. Both assertin and reason are true and reason is the correct explanation of assertion
B. Both assertion and reason are true but reason is not the correct explanation of assertion
C. Assertion is true but reason is flase
D. Both assertion and reason are false

Explanation

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

### Step 1: Analyze the Assertion
The assertion states that "The mirrors used in search lights are parabolic and not concave spherical."

- **Explanation**: Parabolic mirrors are preferred in search lights because they can focus parallel rays of light (like those from a distant source) to a single point (the focus). This property allows for a more concentrated beam of light, which is essential for search lights. In contrast, a concave spherical mirror does not focus all incoming parallel rays to the same point due to its spherical shape.

### Step 2: Analyze the Reason
The reason states that "In a concave spherical mirror, the image formed is always virtual."

- **Explanation**: This statement is incorrect. A concave mirror can form both real and virtual images depending on the position of the object. When the object is placed beyond the center of curvature, a real image is formed. When the object is placed between the focal point and the mirror, a virtual image is formed. Therefore, the reason provided is false.

### Step 3: Conclusion
Based on the analyses:
- The assertion is true: Parabolic mirrors are indeed used in search lights.
- The reason is false: A concave spherical mirror can form both real and virtual images.

Thus, the correct answer is that the assertion is true, but the reason is false.

### Final Answer
The correct option is C: Assertion is true, Reason is false.

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