What role does echo sounder technology play in navigation?

Echo sounder technology is a crucial tool in navigation, primarily because it measures the depth of water beneath a vessel. This depth measurement is vital for safe navigation, as it helps mariners determine whether there is enough water to avoid grounding, particularly in shallow areas or near coastlines. By using sonar technology to send sound waves to the seafloor and then listening for the echo that returns, echo sounders can provide real-time data about the depth, allowing navigators to make informed decisions regarding their course and speed.

While locating other vessels, detecting weather changes, and providing visual cues might be important for navigation, those functions are not associated with the capability of echo sounders. Echo sounders specifically focus on underwater topography and water depth, making option B the correct answer in this context.