The stain used to visualise mitochondria is

Options

A. fast green
B. safranin
C. acetocarmine
D. janus green

Explanation

**Step-by-Step Solution:**

1. **Understanding Stains**: A stain is a dye that is used to impart color to microscopic structures, allowing them to be visualized more clearly under a microscope. This is especially important for smaller or transparent structures that are difficult to see without staining.

2. **Identifying the Stain for Mitochondria**: The question specifically asks for the stain used to visualize mitochondria. Mitochondria are organelles in cells that are involved in energy production and are crucial for various metabolic processes.

3. **Options Provided**: The options given in the question are:
- Fast Green
- Safranin
- Acetocarmin
- Janus Green

4. **Selecting the Correct Stain**: Among the options, Janus Green is known to be a super vital stain that specifically targets mitochondria. It is used to demonstrate the oxidation-reduction reactions that occur within mitochondria, making it the appropriate choice for visualizing these organelles.

5. **Conclusion**: Therefore, the stain used to visualize mitochondria is **Janus Green**.

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