Final answer:
In jet drive boats, the moving parts of the propulsion system, such as propellers or rotor blades, can create hazards for human workers and marine life.
Step-by-step explanation:
In jet drive boats, a hazard can be created by the moving parts of the propulsion system, such as propellers or rotor blades. These moving parts can pose a danger to both human workers and marine life. For example, the rotating propeller blades can potentially harm marine creatures that come into contact with them.