What is the correct sequence of the parts of the eye that the light rays cross in reaching the retina ?

Options

A. Pupil `to` Cornea `to` aqueous humour `to` lens `to` vitreous humour
B. Lens `to` cornea `to` aqueous humour `to` vitreous humour `to` pupil
C. Aqueous humour `to` vitreous humour `to` cornea `to` pupil `to` lens
D. Cornea `to` aqueous humour `to` pupil `to` lens `to` vitreous humour

Answer

To determine the correct sequence of parts of the eye that light rays cross in reaching the retina, we can follow these steps:

### Step-by-Step Solution:

1. **Cornea**: The first part that light rays encounter when they enter the eye is the cornea. The cornea is a clear, dome-shaped surface that covers the front part of the eye and helps to focus the light.

2. **Aqueous Humor**: After passing through the cornea, the light rays travel through the aqueous humor, which is the clear fluid found in the anterior chamber of the eye. This fluid helps maintain intraocular pressure and provides nutrients to the eye.

3. **Pupil**: Next, the light rays pass through the pupil. The pupil is the opening in the center of the iris, which is the colored part of the eye. The iris controls the size of the pupil and thus regulates the amount of light entering the eye.

4. **Lens**: After the pupil, the light rays hit the lens. The lens is a transparent structure that further focuses the light rays onto the retina. It adjusts its shape to ensure that light is properly focused.

5. **Vitreous Humor**: Following the lens, the light rays travel through the vitreous humor. This is a clear, jelly-like substance that fills the space between the lens and the retina, helping to maintain the shape of the eye.

6. **Retina**: Finally, the light rays reach the retina, which is the light-sensitive layer at the back of the eye. The retina converts the light rays into electrical signals that are sent to the brain for visual processing.

### Correct Sequence:
The correct sequence of parts of the eye that light rays cross in reaching the retina is:
1. Cornea
2. Aqueous Humor
3. Pupil
4. Lens
5. Vitreous Humor
6. Retina

### Answer:
The correct sequence is: **Cornea → Aqueous Humor → Pupil → Lens → Vitreous Humor → Retina**.