In front of the lens, the aperture surrounded by the iris is called the

Options

A. pupil
B. retina
C. ciliary body
D. ganglion

Answer

To solve the question "In front of the lens, the aperture surrounded by the iris is called the," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Eye**:
- The eye has several important components, including the lens, iris, pupil, retina, ciliary body, and ganglion cells. Understanding where these components are located is crucial.

2. **Identify the Iris**:
- The iris is the colored part of the eye that surrounds the pupil. It controls the size of the pupil and, consequently, the amount of light that enters the eye.

3. **Locate the Aperture Surrounded by the Iris**:
- The aperture that is surrounded by the iris is the opening that allows light to enter the eye. This opening is known as the pupil.

4. **Evaluate Other Options**:
- The question provides other options: retina, ciliary body, and ganglion.
- The **retina** is located at the back of the eye and is responsible for sensing light and sending signals to the brain.
- The **ciliary body** is located near the lens and is involved in focusing the lens but is not the aperture itself.
- **Ganglion cells** are part of the retina and are not directly related to the aperture.

5. **Conclude the Correct Answer**:
- Since the aperture surrounded by the iris is indeed the pupil, the correct answer to the question is "pupil."

### Final Answer:
The aperture surrounded by the iris is called the **pupil**.

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