What significant design aspect improves the aerodynamic efficiency of the Airbus A220?

High aspect ratio wings are crucial in enhancing the aerodynamic efficiency of the Airbus A220. These wings are designed with a greater length-to-width ratio, which reduces induced drag and allows for improved lift-to-drag performance during flight. By providing better lift characteristics, the high aspect ratio wings enable the aircraft to operate more efficiently at various speeds, particularly during cruise.

This design feature contributes to better fuel economy and overall performance, making the A220 more competitive in the regional jet market. While other options like shorter fuselages or composite materials may contribute to the aircraft's overall efficiency and performance, it is the high aspect ratio wings that play a pivotal role in its aerodynamic efficiency specifically. Variable sweep wings are typically found in military aircraft rather than in commercial designs like the A220, further underscoring the significance of the wing design in this context.