How can you tell if a marine engine is carburated or fuel injected?

Manufacturers like to brag about their fuel injection to sell more boats, so the easiest way is to look for EFI or MPFI on the engine cover. Other than that, fuel injectors are electronic, so they will have extra wires going to them and the sensors that accompany them. A carburetor might have 2 wires going to an electric choke if that.