Assertion : Point sources form only camera .
Reason : Umbra is formed due to the rectilinear propagation of light .

Options

A. A and R are true R is the correct explanation of A .
B. A and R are true but R is not the correct explanation of A.
C. A is false and R is true .
D. Both A and R are false .

Answer

To analyze the assertion and reason provided in the question, let's break it down step by step.

### Step 1: Understanding the Assertion
The assertion states that "Point sources form only camera." This means that a pinhole camera, which acts as a point source, can create images of objects.

### Step 2: Understanding the Reason
The reason given is "Umbra is formed due to the rectilinear propagation of light." Umbra refers to the darkest part of a shadow where the light source is completely blocked. The rectilinear propagation of light means that light travels in straight lines.

### Step 3: Connecting the Assertion and Reason
In a pinhole camera, light from a point source passes through a small opening (the pinhole) and projects an image on the opposite side. The image formed is indeed a type of shadow known as umbra, which occurs because light travels in straight lines and creates a distinct boundary between light and dark areas.

### Step 4: Conclusion
Both the assertion and the reason are true. The assertion is correct because a pinhole camera can form images from point sources, and the reason is also correct as umbra is formed due to the straight-line travel of light. Therefore, the assertion is supported by the reason.

### Final Answer
Both the assertion and the reason are true, and the reason correctly explains the assertion.

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