The correct answer is C) Both "A" and "B". Desuperheated steam can occur in a spray attemperator (A) and in main engine extractions (B). 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 extracted from the main engine for use in other shipboard systems, can also lead to desuperheated steam as the extracted steam loses some of its superheat. The other options are incorrect because a spray attemperator and main engine extractions are both locations where desuperheated steam can occur, so the correct answer is C, encompassing both A and B.