Axial filament of sperm is formed by

Options

A. Distal centriole
B. Proximal centriole
C. Mitoc hondrial spiral
D. DNA.

Answer

### Step-by-Step Solution:

1. **Understanding Axial Filament**: The axial filament of sperm is an important structure that forms part of the flagellum, which is essential for the movement of sperm.

2. **Identifying the Components of Sperm**: The sperm consists of several parts: the acrosome, head, neck, and tail. The axial filament is located in the tail region of the sperm.

3. **Role of Centrioles**: In the neck region of the sperm, there are two centrioles: the proximal centriole and the distal centriole. Each has distinct functions.

4. **Function of the Proximal and Distal Centrioles**:
- The **proximal centriole** is involved in the first cleavage of the zygote and helps in the formation of the mitotic spindle.
- The **distal centriole** is responsible for the formation of the axial filament.

5. **Conclusion**: Since the axial filament of sperm is formed by the distal centriole, the correct answer to the question is that the axial filament of sperm is formed by the distal centriole.