Important Defects of Vision

There are several important defects of vision that can affect individuals. These include presbyopia, myopia, and hypermetropia. The correct answer is option 'D', which states that all of these defects are important.

Presbyopia:
Presbyopia is a condition that commonly occurs with age. It is caused by the natural aging process of the lens in the eye, which becomes less flexible and loses its ability to focus on nearby objects. People with presbyopia often experience difficulty reading small print or doing close-up tasks. This condition can be easily corrected with the use of reading glasses or contact lenses.

Myopia:
Myopia, also known as nearsightedness, is a condition in which individuals can see nearby objects clearly but have difficulty seeing distant objects. It occurs when the eyeball is too long or the cornea is too curved, causing light to focus in front of the retina instead of directly on it. Myopia can be corrected with the use of glasses or contact lenses that help to redirect the light onto the retina, allowing for clear vision.

Hypermetropia:
Hypermetropia, also known as farsightedness, is the opposite of myopia. Individuals with hypermetropia can see distant objects clearly but have difficulty focusing on nearby objects. This condition occurs when the eyeball is too short or the cornea is too flat, causing light to focus behind the retina instead of directly on it. Hypermetropia can be corrected with the use of glasses or contact lenses that help to bring the focus of light onto the retina.

All of these defects, presbyopia, myopia, and hypermetropia, have a significant impact on an individual's ability to see clearly. They can cause blurred vision, eye strain, headaches, and difficulty with daily tasks such as reading or driving. It is important for individuals with these vision defects to have regular eye examinations and wear corrective lenses as prescribed by an eye care professional.

In conclusion, the correct answer is option 'D' because all of these defects, presbyopia, myopia, and hypermetropia, are important and can significantly affect an individual's vision.