Presbyopia occurs as a result of the following: (A) Shoening of eye ball, (B) Hardening of lens, (C) Thinning of the lens, (D) Lengthening of eye ball
Answer is B. Presbyopia (eyesight of old age) is not an error of refraction but a condition of physiological insufficiency of accommodation leading to a progressive fall in near vision. The cause of presbyopia is believed to be due to thickening and loss of flexibility of the lens in the eye. Reference: AK khurana 7th edition