Some persons have difficulty to see the objects in dim light during night. This is due to the lack of vitamin A in the diet and improper functioning of rod-shaped cells. The rod-shaped cells respond to intensify variation in light. These days, it is possible to correct the defect of vision by using contact lenses.
(i) Identify the defect of eye.
(ii) 'The people with this defect of eye are treated with care and proper diet.' Suggest two reasons.
