Which method includes forming lines of people to search an area effectively?

The method that includes forming lines of people to search an area effectively is human chains. This technique involves organizing individuals into a continuous line that stretches across the search area, allowing for a systematic and thorough search of the terrain. Each person in the line can focus on a specific section of the area, ensuring that no spots are missed and that the group can effectively cover large areas.

Human chains are particularly effective in surface water rescue scenarios, as they enable rescuers to coordinate their efforts while maintaining visibility and communication with one another. This approach is essential in ensuring safety and efficiency during a search operation, especially in potentially hazardous environments where visibility may be limited or where water currents may pose additional challenges.

In contrast, other methods like probing, sonar, and dragging serve different purposes within a search and rescue operation. Probing is typically used to feel for submerged objects or victims, sonar involves using sound waves to detect submerged items, and dragging is a technique that might involve using equipment to retrieve objects from the water. While each method has its unique advantages, human chains specifically capitalize on teamwork and organization for effective area searches.