In a similarity with photographic camera, retina acts as
(a) Shutter
(b) Lens
(c) Diaphragm
(d) Film

Options

A. Shutter
B. Lens
C. Diaphragm
D. Film.

Answer

To solve the question "In a similarity with photographic camera, retina acts as," we need to analyze the functions of the components of both a photographic camera and the human eye.

### Step-by-Step Solution:

1. **Understand the Function of the Retina**: The retina is a light-sensitive layer at the back of the eye where the image is formed. It captures light and converts it into neural signals that are sent to the brain for processing.

2. **Compare with a Photographic Camera**: In a photographic camera, the film (or digital sensor in modern cameras) is the component that captures the image. Just like the retina in the eye, the film is where the image is formed after light passes through the lens.

3. **Analyze the Options**:
- **(a) Shutter**: The shutter controls the duration of light exposure but does not capture the image.
- **(b) Lens**: The lens focuses light onto the film or sensor but does not capture the image itself.
- **(c) Diaphragm**: The diaphragm regulates the amount of light entering the camera but does not capture the image.
- **(d) Film**: The film captures the image, similar to how the retina captures the image in the eye.

4. **Conclusion**: Since the retina functions similarly to the film in a camera by capturing the image, the correct answer is (d) Film.

### Final Answer:
The retina acts as (d) Film in similarity with a photographic camera.

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