The largest moon in solar system is of Saturn:

Options

A. Titan
B. Earth's Moon
C. Ceres
D. Sirius

Explanation

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about the largest moon in the solar system that belongs to Saturn.

2. **Recall Information About Saturn's Moons**: Saturn has many moons, but we need to focus on the largest one.

3. **Identify the Largest Moon of Saturn**: The largest moon of Saturn is Titan.

4. **Confirm the Size of Titan**: Titan is not only the largest moon of Saturn but also the second-largest moon in the entire solar system, after Ganymede, which is a moon of Jupiter.

5. **Conclude the Answer**: Therefore, the correct answer to the question is Titan.

**Final Answer**: The largest moon of Saturn is Titan.

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