Answer the following questions.
How does the defect of myopia arise in a human eye?

Explanation

### Step-by-Step Solution:

1. **Understanding Myopia**: Myopia, also known as nearsightedness, is a common vision condition where distant objects appear blurry while close objects can be seen clearly. This condition arises when the eye is too powerful for its length.

2. **Image Formation**: In a normal eye, light rays from distant objects are focused directly on the retina. However, in myopia, the light rays converge before they reach the retina, causing the image to form in front of it.

3. **Causes of Myopia**:
- **Ciliary Muscles**: The ciliary muscles in the eye control the shape of the lens. If these muscles do not relax properly, the lens remains too curved, which increases the eye's optical power. This means that the focal length of the lens is too short, causing images of distant objects to focus in front of the retina.
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