Who gave the lamellar or sandwich model of cell membrane ?

Options

A. Singer and Nicolson
B. Danielli and Davson
C. J.Robertson
D. None of these

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the scientists who proposed the lamellar or sandwich model of the cell membrane.

2. **Identifying the Model**: The sandwich model describes the structure of the cell membrane, which consists of a phospholipid bilayer sandwiched between two layers of proteins.

3. **Recognizing the Scientists**: The sandwich model was proposed by two scientists, Daniel and Davison.

4. **Describing the Model**: According to this model, the phospholipid layer is situated between two protein layers, resembling a sandwich. This arrangement helps explain the fluidity and functionality of the cell membrane.

5. **Conclusion**: Therefore, the correct answer to the question is that the lamellar or sandwich model of the cell membrane was given by Daniel and Davison.

### Final Answer:
The lamellar or sandwich model of the cell membrane was proposed by Daniel and Davison.