Answer:
Ca is a reducing agent and O is the oxidizing agent.
Step-by-step explanation:
calcium is the reducing agent as it reduces oxygen while it oxidize itself and oxygen is an oxidising agent because it oxidized others and reduces itself. in this equation oxygen is reducing and Calcium is oxidising. and as it is stated in the definition that oxidizing agent is the agent which oxidises others and reduces itself and it is also stated that reducing agent reduces others and oxidize itself. so based on this statement calcium is reducing agent and O is a oxidizing agent.