The correct option is (c).
Explanation
The human eye acts as a complex optical instrument that focuses light onto the retina to form an image. Its structure includes protective layers, a focusing mechanism involving the lens and muscles, and a neural pathway for signal transmission to the brain.
Statement-wise Analysis:
- Statement 1 is Correct. The outer coat of the eye is known as the sclera. It is a tough, white, fibrous layer that maintains the shape of the eyeball and protects the delicate inner structures from mechanical injury.
- Statement 2 is Incorrect. The ciliary muscles are responsible for modifying the curvature of the eye lens to adjust its focal length (a process called accommodation). They do not control the eyelids. The movement of the eyelids is controlled by different muscles, such as the levator palpebrae superioris and the orbicularis oculi.
- Statement 3 is Correct. The optic nerve connects the eye to the brain. It transmits electrical signals (visual impulses) generated by the photoreceptor cells (rods and cones) in the retina to the visual cortex of the brain for processing.
Key Takeaway:
The sclera provides external protection, the ciliary muscles facilitate accommodation by adjusting the lens, and the optic nerve serves as the communication link between the retina and the brain.