Which is the brightest star in the sky ?

Options

A. Cassiopeia
B. Orion
C. Sirius
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the brightest star in the sky. It's important to identify the correct star among the options provided.

2. **Identifying the Options**: The options given are Fulmsa, Cassiopeia, Orion, Sirius, and none of these.

3. **Researching the Stars**: To determine which star is the brightest, we need to consider the known stars and their brightness.

4. **Identifying Sirius**: Among the options, Sirius is known as the brightest star in the night sky. It is often referred to as the "Dog Star" and is part of the constellation Canis Major.

5. **Confirming the Brightness**: Sirius is classified as a main-sequence star and has a magnitude of -1.46, making it the brightest star visible from Earth.

6. **Conclusion**: Based on the information, the correct answer to the question is Sirius.

**Final Answer**: The brightest star in the sky is Sirius.

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