Question 9 (a) What is a callback function in event driven computing? 2 marks] (b) In event driven programming, list three possible classes of events to be han- [2 marks] (c) An event driven program (such as used by graphical user interfaces) has the dled in typical graphical user interfaces. following typical structure in the main loop: int main...) setup main_loop); I1 vhy do you need this? return 0; // set callback functions What is the goal of the function main loop in the event driven program above? [2 marks]