The correct answer is C) Both "A" and "B". Desuperheated steam can occur in a spray attemperator and in main engine extractions. A spray attemperator is a device used to reduce the temperature of superheated steam by injecting a fine mist of water, which causes the steam to become desuperheated. Main engine extractions, where steam is taken from the main engine for use in other shipboard systems, can also result in desuperheated steam as the steam pressure and temperature are reduced. The other options are incorrect because a spray attemperator is specifically designed to desuperheat steam, and main engine extractions are a common location where desuperheated steam can occur on a vessel.