Largest cell is

Options

A. Ostrich egg
B. Mycoplasma cell
C. Bacterial cell
D. All of these

Explanation

**Step-by-Step Solution:**

1. **Identify the Options**: The question asks for the largest cell among the following options: ostrich egg, mycoplasma cell, bacterial cell, or all of these.

2. **Analyze Each Option**:
- **Ostrich Egg**: The ostrich egg is known to be the largest single cell in the world. It has a diameter of about 15 to 20 centimeters and weighs approximately 1.4 kilograms.
- **Mycoplasma Cell**: This is a type of bacteria and is one of the smallest known cells, with a diameter of around 0.4 micrometers.
- **Bacterial Cell**: Bacterial cells vary in size, but on average, their diameter ranges from 0.5 to 2.0 micrometers, which is still much smaller than an ostrich egg.
- **All of These**: This option implies that all listed cells are the largest, which is not correct since the ostrich egg is significantly larger than the others.

3. **Conclusion**: After analyzing the sizes of the cells mentioned, it is clear that the ostrich egg is the largest cell among the options provided.

4. **Final Answer**: The largest cell is the ostrich egg.

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