Which task is essential for maintaining fuel efficiency?

Monitoring and controlling fuel consumption is essential for maintaining fuel efficiency because it directly impacts how much fuel is used during a flight. By keeping track of fuel usage, crew members can identify patterns and implement strategies to optimize fuel burn, such as adjusting flight paths, speeds, or power settings. This practice not only ensures that fuel is used efficiently but also helps in planning for fuel reserves needed for safe operations.

Additionally, effective fuel management can lead to cost savings and reduced environmental impact, making it a critical task within aviation operations. The other choices, while they may have some relation to operational efficiency, do not address fuel consumption directly in the same manner that monitoring and controlling it does.