When must you stop your boat while approaching a marina?

Stopping your boat at a no-wake zone or when instructed by marina personnel is essential for safety and compliance with navigational rules. No-wake zones are designated areas where boats must operate at low speeds to minimize the wake they produce, which helps reduce erosion, protect wildlife, and ensure the safety of other vessels, especially in congested areas like marinas.

When marinas have personnel directing boat traffic, following their instructions is crucial as they are trained to manage boat movements effectively. This helps to maintain order and prevents accidents as boats navigate through areas where many other vessels are maneuvering, making it safer for everyone involved.

The other options describe situations that may not consider the specific regulations designed for safely navigating near marinas. Simply stopping just before entering the marina area or waiting until you see the dock might not allow adequate time to adjust your speed to ensure a safe approach, whereas only seeing other boats isn't a definitive or safe trigger for stopping.