Answer
This is a redox reaction. Mg acts as a reducing agent and Fe2+ acts as an oxidizing agent.
Work Step by Step
In a redox reaction, there is a change in the oxidation number. Mg's oxidation number changes from 0 to +2. There is an increase in the oxidation number so it gets oxidised. Hence, it acts as a reducing agent.
Fe2+ oxidation number changes from +2 to 0. There is a decrease in the oxidation number, it gets reduced. Hence, it acts as an oxidizing agent.