The correct option is C Fe2O3 is an oxidising agent.
Oxidising agent :
Substance which oxidises others and itself gets reduced.
Reducing agent :
Substance which reduces others and itself gets oxidised.
+3Fe2O3 (s)+20Al (s)→+3Al2O3 (s)+20Fe (s)
In the above reaction we can see that Fe in gets reduced from +3 to 0 and Al gets oxidised from 0 to +3
Al reduces Fe and itself gets oxidised so it is called reducing agent, while Fe2O3 oxidises Al and itself gets reduced , so it is called an oxidising agent.