Explanation: Functional testing of a SART (Search and Rescue Transponder) should be minimized primarily because it transmits a signal on the 9 GHz X-band radar frequency. Firstly, this signal can appear on other vessels' radar displays, potentially masking legitimate navigational targets and interfering with safe navigation. This creates a collision risk or other hazards. Secondly, the SART signal is specifically designed to indicate a distress situation and aid in rescue. A test transmission could be misinterpreted as an actual emergency, prompting unnecessary search and rescue efforts and diverting resources from real incidents. Lastly, SARTs are battery-powered emergency devices. Minimizing testing helps preserve the critical battery life required for genuine distress situations. Therefore, option D is correct as it comprehensively addresses these key concerns: potential interference with safe navigation, the possibility of misinterpretation as an actual Distress, and the inherent need to minimize power consumption by limiting transmissions. Option A is incorrect because "notifying other vessels of an actual Distress" is the SART's *purpose* in an emergency, not a reason to minimize *testing*; testing causes *misinterpretation*. Option B is incorrect as testing at sea increases the likelihood of interference and confusion, rather than reducing it. Option C is incomplete, as it omits the interference aspect and implies that testing in port completely prevents issues, which is not true.