What causes Presbyopia?

Presbyopia is primarily caused by the hardening of the lens in the eye. As people age, the natural lens becomes less flexible and more rigid, which makes it increasingly difficult to focus on nearby objects. This loss of elasticity in the lens prevents the eye from adjusting its focal point as effectively, leading to difficulty in tasks such as reading or seeing items up close.

In the context of the other options, a sudden increase in intraocular pressure typically relates to conditions like glaucoma rather than presbyopia. Lens clouding, known as cataracts, can also impair vision but does so in a different manner compared to the focusing difficulties associated with presbyopia. Gradual increases in intraocular pressure may also suggest glaucoma or other eye issues but are not directly related to the age-related difficulty in focusing on close objects that defines presbyopia.