Which one of the following four metals would be displaced from the solution of its salts by other three metals? 

Options

A. Mg
B. Ag
C. Zn
D. Cu

Explanation

To determine which metal would be displaced from the solution of its salts by the other three metals, we need to analyze the reactivity of the given metals: Ag (silver), Mg (magnesium), Zn (zinc), and Cu (copper).

### Step-by-Step Solution:

1. **Understand Displacement Reactions**: Displacement reactions occur when a more reactive metal displaces a less reactive metal from its salt solution. This is based on the reactivity series of metals.

2. **Identify the Metals**: The metals in question are:
- Ag (silver)
- Mg (magnesium)
- Zn (zinc)
- Cu (copper)

3. **Refer to the Reactivity Series**: The reactivity series ranks metals from most reactive to least reactive. In general, the order is:
- Mg > Zn > Cu > Ag
This means magnesium is the most reactive, followed by zinc, then copper, and finally silver.

4. **Determine the Least Reactive Metal**: From the reactivity series, we can see that silver (Ag) is the least reactive metal among the four listed.

5. **Conclusion**: Since silver is the least reactive, it would be displaced from its salt solution by the other three metals (magnesium, zinc, and copper). Therefore, the correct answer is silver (Ag).

### Final Answer:
The metal that would be displaced from the solution of its salts by the other three metals is **Ag (silver)**.

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