Which is an optical aid for people who suffer from partial loss of vision?

Options

A. Bifocal lens
B. Braille system
C. Talking watch
D. Cassette

Answer

**Step-by-Step Solution:**

1. **Understanding Partial Loss of Vision**:
- Partial loss of vision refers to a condition where a person can see but not clearly. This can include difficulties in seeing objects at a distance (myopia) or difficulties in seeing objects up close (hypermetropia).

2. **Identifying Optical Aids**:
- Optical aids are devices designed to assist individuals with vision problems. Common examples include glasses, contact lenses, and magnifying devices.

3. **Evaluating the Options**:
- The question mentions several aids: cassettes (not relevant), talking watches (not for vision), Braille (for the blind), and bifocal lenses.

4. **Understanding Bifocal Lenses**:
- Bifocal lenses are designed to correct vision for individuals who have both myopia and hypermetropia. They have two different optical powers: one for distance vision and one for near vision.

5. **Conclusion**:
- Bifocal lenses are specifically designed to help individuals with partial loss of vision, allowing them to see both near and far. They are particularly useful for people over the age of 40 who often experience presbyopia, a condition where the eye's lens loses flexibility.

6. **Final Answer**:
- The optical aid for people who suffer from partial loss of vision is **bifocal lenses**.

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