In MATLAB/Simulink, The model must be BUILT 1st before it can be run. Building involves generating and compiling the real time code. To do this you can just use A. CTRL+B. B. ALT+B. C.SHIFT+B. Solution CTRL+B means build model(code genaration) For new modal building involves both generating and compiling the real time code we use ctrl+B So option A is correct.