Soap box-like overlapping shells are found in the cell walls of

Options

A. dinoflagellates
B. protozoan
C. diatoms
D. euglenoids

Answer

To answer the question regarding which organism has soap box-like overlapping shells in their cell walls, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Structure**: The question describes a structure that resembles a soap box, which indicates a specific arrangement of cell walls.

2. **Recognize the Organism**: The organism that is known for having such a structure is diatoms. Diatoms are a group of microalgae that have unique cell walls.

3. **Understand the Composition**: The cell walls of diatoms are composed of silica (silicon dioxide), which gives them a glass-like appearance. This is a key characteristic that distinguishes diatoms from other organisms.

4. **Describe the Shells**: The cell wall of diatoms consists of two overlapping shells:
- The upper shell is called the **Epitheca**.
- The lower shell is known as the **Hypotheca**.
These two shells fit together in a manner that resembles a soap box.

5. **Conclude the Answer**: Based on the above points, the answer to the question is that the soap box-like overlapping shells are found in the cell walls of **diatoms**.

### Final Answer:
**Diatoms**