The correct answer is C) Electric. Smaller gas turbine engines, such as those used in marine applications, commonly use electric starters. Electric starters are preferred for their simplicity, reliability, and ease of integration with the engine's electrical system. They convert electrical energy into mechanical rotation to start the engine. The other options are less commonly used in this application. Pneumatic and air turbine starters are more commonly found on larger gas turbine engines, while hydraulic starters are typically used for diesel engines rather than gas turbines.