8. d, all of the above. Refractive surgery can be done either mechanically using special surgical tools or by laser. Laser refractive surgery can correct nearsightedness, farsightedness and astigmatism. There is not yet an effective treatment for presbyopia because this condition is caused by failure of the lens to accommodate rather than problems with the shape of the cornea.

9. c, diabetes. The condition is called diabetic retinopathy.

10. b, an ophthalmologist. An ophthalmologist is the only eye-care professional qualified to perform surgery.

Source: Pure Matters