<human>:  What's the most fuel-efficient route from A to B?
<bot>: The most fuel-efficient route from A to B depends on a few factors, such as the terrain and the type of vehicle being used. Additionally, drivers may want to consider the estimated traffic and construction in the area to identify the most efficient route. It may be helpful to use online mapping services or navigation systems to consider the route that takes the least amount of time and uses the least amount of fuel.