The latest model of cell membrane is the

Options

A. Unit membrane model
B. Fluid mosaic model
C. Danielli and Davson's model
D. Robertson's model.

Explanation

To answer the question "The latest model of cell membrane is the", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Options**: The question provides several options for the models of the cell membrane:
- Unit Membrane Model
- Fluid Mosaic Model
- Davson-Danielli Model
- Robertson Model

2. **Understand the Models**:
- **Unit Membrane Model**: This model describes the cell membrane as a lipid bilayer with proteins on its surface.
- **Fluid Mosaic Model**: This is the currently accepted model that describes the cell membrane as a dynamic and flexible structure with various proteins embedded in or attached to a fluid lipid bilayer.
- **Davson-Danielli Model**: An earlier model that suggested a lipid bilayer sandwiched between two layers of proteins.
- **Robertson Model**: This model also describes a similar structure to the Unit Membrane Model.

3. **Identify the Latest Model**:
- The Fluid Mosaic Model was proposed in 1972 by S.J. Singer and G.L. Nicolson. It is the most accepted and widely recognized model of the cell membrane today.

4. **Conclusion**: Based on the information above, the latest model of the cell membrane is the **Fluid Mosaic Model**.

### Final Answer:
The latest model of the cell membrane is the **Fluid Mosaic Model**.

---