Which type of light would be set up in rivers and isolated locations?

The correct option is Minor Lights, which are typically used in rivers and isolated locations to aid navigation. These lights are less intense than major lights and are intended to mark channels, hazards, or specific points of interest in less trafficked or navigationally complex areas. Their primary goal is to provide sailors with guidance and ensure safety in environments where larger navigational aids may be unnecessary or impractical.

In contrast, major lights are generally found in prominent coastal locations, guiding vessels on open waters and serving as significant reference points due to their higher visibility over long distances. Sector lights are designed to show different colors in varying directions and are specifically used to indicate safe navigational routes where navigational hazards exist. Beacon lights, often simple, fixed structures, may be used as point sources of light but do not serve the same comprehensive purpose as minor lights within inland waterways or remote locations. Thus, minor lights are the most appropriate choice for aiding navigation in rivers and isolated areas.