Which of the following best distinguishes an Emergency Shutdown (ESD) from a normal, planned shutdown?

1. An ESD is performed using only software commands, while a normal shutdown involves physical switches.
2. An ESD prioritizes bringing the system to a safe, non-hazardous state immediately, potentially sacrificing the test article or data, whereas a normal shutdown is an orderly process to preserve system state and data.
3. An ESD can only be initiated by the Test Director, while a normal shutdown is initiated by the Test Conductor.
4. An ESD must be completed within 60 seconds, whereas a normal shutdown has no time limit.