Question EASA Drone License A2 - Flight performance and planning

80 - EASA Drone A2 License - According to the '1:1 rule' for ground risk mitigation, how does increasing flight altitude affect the required horizontal safety buffer?

The horizontal distance remains constant regardless of flight altitude

The horizontal buffer must increase proportionally with altitude, as a drone falling from a greater height has a wider potential impact radius

The buffer can decrease because hitting people is less likely from a high altitude

The rule only applies during automatic takeoff and landing phases