What must pilots do after receiving a "Hold Short" instruction?

After receiving a "Hold Short" instruction, pilots must stop before the designated point, which is typically a runway or another critical area where aircraft movements are restricted. This instruction is crucial for ensuring safety and maintaining the controlled flow of traffic on the airport surface. By stopping as instructed, pilots allow for other aircraft or vehicles to safely operate within those restricted areas, thus preventing potential collisions or incidents. Holding short is an essential procedure that helps maintain the operational integrity of the airport environment.

Other options, such as proceeding to the runway, taking off immediately, or communicating with ground control, do not align with the specific meaning of a "Hold Short" instruction and may lead to violations of air traffic procedures. Enhanced communications with ground control is important, but the primary action that must occur after receiving this instruction is to halt at the designated location.