How does a higher lift-to-drag ratio affect an aircraft's fuel efficiency?

A higher lift-to-drag ratio significantly enhances an aircraft's fuel efficiency because it indicates that the aircraft can generate more lift relative to the drag it experiences during flight. When an aircraft has a high lift-to-drag ratio, it can maintain level flight or gain altitude with less engine power, which means it needs less fuel to overcome aerodynamic resistance. This efficiency translates to an increased operational range, enabling the aircraft to fly farther on a given amount of fuel.

In contrast, the other options do not align with the impact of a high lift-to-drag ratio. A reduction in maximum speed is not a direct consequence since a higher lift-to-drag ratio primarily benefits efficiency rather than limiting speed. Similarly, a higher lift-to-drag ratio does not inherently increase the weight of the aircraft or improve maneuverability, which are influenced by other factors such as aircraft design and flight conditions.