The least distance of distinct vision for a normal person is about

Options

A. 1 m
B. 0.5 m
C. 0.25 m
D. none of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Concept**: The least distance of distinct vision refers to the closest distance at which the human eye can focus on an object clearly without strain.

2. **Identifying the Standard Distance**: For a normal person, this distance is generally accepted to be around 25 cm. This means that if an object is placed closer than this distance, the eye will struggle to focus, resulting in a blurred image.

3. **Explaining the Eye's Mechanism**: When an object is closer than 25 cm, the ciliary muscles in the eye have to work harder to adjust the lens for focusing. This can lead to eye strain and discomfort.

4. **Verifying the Options**: The question provides several options:
- 1 meter
- 0.5 meter
- 0.25 meter (which is equivalent to 25 cm)

5. **Selecting the Correct Answer**: Since 25 cm is the least distance of distinct vision for a normal person, the correct option is 0.25 m.

**Final Answer**: The least distance of distinct vision for a normal person is about 25 cm, or 0.25 m.

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