The correct option is (c) 2 and 3 only.
Explanation
The human eye functions as a natural optical instrument. Maintaining its health requires appropriate lighting conditions, protection from high-intensity radiation, and proper hygiene to prevent physical injury to the cornea and retina.Statement 1 is Incorrect: Visual acuity refers to the clarity or sharpness of vision. Too little light (dim lighting) causes eye strain and headaches because the eye muscles must work harder to focus. Furthermore, the cone cells in the retina, which are responsible for high visual acuity and color vision, require adequate light levels to function effectively. Therefore, insufficient light reduces, rather than improves, visual acuity.
Statement 2 is Correct: Looking directly at the Sun can cause permanent damage to the retina, a condition known as solar retinopathy. The eye's lens focuses the Sun's high-intensity visible light and ultraviolet (UV) radiation onto a small point on the retina (the fovea), potentially causing thermal or photochemical burns to the light-sensitive cells.
Statement 3 is Correct: If dust or a foreign particle enters the eye, rubbing it can cause the particle to scratch the delicate corneal surface, leading to abrasions or infections. The correct first aid measure is to flush the eye gently with clean water to dislodge and wash away the irritant.
Key Takeaway: Optimal eye care involves ensuring sufficient illumination for reading or work, avoiding direct exposure to intense light sources like the Sun, and using clean water to remove foreign bodies rather than rubbing the eyes.