The correct answer is C) saturated and superheated steam. Most marine boilers are designed to produce both saturated and superheated steam. Saturated steam is steam at the boiling point of water at a given pressure, while superheated steam is steam that has been heated to a temperature above the boiling point. Marine boilers typically have sections that produce both types of steam to meet the various power and heating needs on board the vessel. The other options are incorrect because: A) marine boilers are not limited to producing only saturated steam, and B) and D) marine boilers do not exclusively produce superheated or supercritical steam.