Explanation:

Statement 1 is incorrect

• GPS Spoofing: A cyberattack that uses false GPS signals to mislead navigation systems.

• It commonly targets drones and disrupts navigation in conflict zones. Attackers mimic legitimate GPS signals, tricking systems into perceiving incorrect locations, speeds, or altitudes.

Statement 2 is incorrect

• GPS Interference: A disruption in the accuracy of GPS signals used for navigation that can be caused by intentional jamming or environmental factors.

Statement 3 is incorrect

• Inertial Reference System (IRS): A self-contained navigation system that provides position, velocity, and orientation without external signals like GPS.

• Key Components: Gyroscopes measure angular velocity for orientation; Accelerometers track linear acceleration to calculate movement.

• Functionality: Integrates data to calculate position relative to a known starting point.

• Significance in Aviation: Acts as a backup system ensuring navigation accuracy and safety during GPS failures or attacks for up to five hours.

Hence option 4th is correct.