Unicellular algae which produce "Auxospores" and have soap box like cell wall are :–

Options

A. Dinoflagellates
B. Euglenoids
C. Diatoms
D. Slime Mould

Answer

To solve the question regarding unicellular algae that produce "Auxospores" and have a soap box-like cell wall, we can follow these steps:

### Step 1: Understand the Key Terms
- **Unicellular Algae**: These are single-celled organisms that perform photosynthesis.
- **Auxospores**: These are specialized spores produced by certain algae, particularly during periods of unfavorable conditions.
- **Soap Box-like Cell Wall**: This describes a specific structure of the cell wall that is characteristic of certain algae.

### Step 2: Analyze the Options
1. **Dinoflagellates**: These are unicellular organisms but they do not produce auxospores and have a different type of cell structure.
2. **Euglenoids**: While they are unicellular, they do not have a cell wall; instead, they have a pellicle, which is a flexible outer layer.
3. **Diatoms**: These are indeed unicellular algae known for their unique silica-based cell walls that resemble soap boxes. They produce auxospores during their life cycle.
4. **Slime Mold**: These are not classified as algae; they resemble protozoa and fungi, thus are not the correct answer.

### Step 3: Identify the Correct Answer
Based on the analysis, the only option that fits both criteria (producing auxospores and having a soap box-like cell wall) is **Diatoms**.

### Final Answer
The unicellular algae which produce "Auxospores" and have a soap box-like cell wall are **Diatoms**.

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