Question

explain with a suitable example the metals used to reduce the following oxides of less reactive metals

Answer 1

metals can reduce the oxides of less reactive metals than them.
ex: 
2Na + CuO = Na2O + Cu

Answer 2

Explanation:

It is known that a more reactive metal can replace a less reactive metal because high reactivity leads to displacement of less  reactive metal.

For example, $Mg + CuO \rightarrow MgO + Cu$

Therefore, here we can see that magnesium being more reactive in nature displaces copper from copper oxide.