From the metals copper, iron, magnesium, sodium and zinc, select from metal which arrange the metals in decreasing order of reactivity.

Explanation

To arrange the metals copper, iron, magnesium, sodium, and zinc in decreasing order of reactivity, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Metals**: We have five metals to consider: Copper (Cu), Iron (Fe), Magnesium (Mg), Sodium (Na), and Zinc (Zn).

2. **Understand Reactivity**: Reactivity of metals generally decreases from left to right in the periodic table. The more reactive metals tend to lose electrons more easily.

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