Which of the following is a preventive measure against EMI?

Grounding is a critical preventive measure against Electromagnetic Interference (EMI). It helps to dissipate unwanted electrical energy into the earth, thereby reducing the potential for EMI to disrupt electronic systems and equipment. By creating a conductive path to ground, grounding ensures that stray electromagnetic fields do not interfere with the operation of sensitive electronic devices. This is particularly important in aviation environments, where EMI can affect navigational and communication systems, thereby compromising safety and operational effectiveness.

Insulation, while it may serve to protect against electrical current and ensure safety, does not directly address the interference caused by electromagnetic fields. Amplification refers to increasing the strength of signals rather than mitigating interference. Calibration relates to adjusting and fine-tuning equipment to ensure precise performance but does not prevent EMI from occurring. Thus, grounding stands out as the most effective and relevant preventive measure against EMI in the context of aviation and electronic systems.