In old age, the vision of eye becomes dim. It is due to

Options

A. Myopia
B. Hypermetropia
C. Cataract
D. Astigmatism

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks why vision becomes dim in old age. We need to identify the condition that is most commonly associated with this phenomenon.

2. **Identifying the Options**: The options provided are myopia, hypermetropia, cataract, and astigmatism. We need to analyze each term to determine which one relates to dim vision in older adults.

3. **Defining Myopia**: Myopia, or near-sightedness, is a condition where close objects are seen clearly, but distant objects appear blurry. This condition can occur in both young and older individuals but is not specifically associated with aging.

4. **Defining Hypermetropia**: Hypermetropia, or far-sightedness, is the opposite of myopia. In this condition, distant objects are seen clearly, while close objects appear blurry. Like myopia, this condition can occur at any age and is not specifically linked to old age.

5. **Defining Cataract**: Cataract is a condition that commonly occurs in older adults. It involves the lens of the eye becoming progressively opaque, leading to blurred vision. This opaqueness is often due to protein denaturation in the lens, which results in a cloudy appearance and dim vision.

6. **Defining Astigmatism**: Astigmatism is a refractive error caused by an irregular shape of the cornea or lens, leading to distorted or blurred vision. While it can occur at any age, it is not specifically associated with aging.

7. **Conclusion**: Based on the definitions and associations, cataract is the condition that is most commonly linked to dim vision in old age. Therefore, the correct answer is cataract.

**Final Answer**: The vision of the eye becomes dim in old age primarily due to cataract.

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