What is one disadvantage of single LZs?

The choice regarding a greater potential for enemy detection accurately identifies a significant disadvantage of using single Landing Zones (LZs). When a single LZ is established, all helicopter landings and operations are concentrated in one location. This concentration makes it easier for enemy forces to monitor and detect helicopter activity, increasing the risk that their movements could be observed and targeted.

In a single LZ scenario, if enemy forces are aware of the location, they can establish positions to watch for incoming aircraft, leading to a higher likelihood of ambush or fire from hostile elements. This threat necessitates careful operational security, as any detection of helicopter activity could compromise the mission and endanger personnel.

The other options, while highlighting valid considerations in military operations, do not directly correlate to the specific risks posed by a single LZ in terms of enemy detection. More complex planning could be true depending on the mission's complexity, and the overall security or firepower concentration could vary depending on a multitude of tactical factors. However, the heightened risk of enemy detection stands out as a clear and critical disadvantage of using a single landing zone.