Final answer:
The most common causes of blindness worldwide are age-related macular degeneration (AMD), cataracts, and trachoma.
Step-by-step explanation:
The most common cause of blindness worldwide is age-related macular degeneration (AMD). This condition occurs when a layer of cells called retinal pigment epithelium dies, leading to the death of the macula, a specialized area near the center of the retina.
Another common cause of blindness is cataracts. Cataracts occur when the lens of the eye becomes clouded, resulting in a loss of vision.
Lastly, trachoma is a leading cause of preventable blindness in developing countries, particularly in Africa and Asia. Trachoma is caused by a bacterium called Chlamydia trachomatis. It spreads through poor sanitation conditions and can lead to inflammation and scarring of the eye.