.......... Is the largest asteroid.

Options

A. Ceres
B. Vesta
C. Sirius
D. Viesta

Explanation

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the largest asteroid.

2. **Consider the Options**: The options provided are Ceres, Vesta, and Ceres and Vesta.

3. **Research the Largest Asteroid**: Ceres is known to be the largest asteroid in the asteroid belt, which is located between the orbits of Mars and Jupiter.

4. **Size Comparison**: Ceres is approximately one-quarter the size of the Moon, which highlights its significant size compared to other asteroids.

5. **Conclusion**: Based on the information, the correct answer to the question is Ceres.

**Final Answer**: Ceres is the largest asteroid.

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