What is "wake turbulence"?

Wake turbulence refers specifically to the disturbances in the atmosphere that are created by an aircraft as it moves through the air. When an aircraft flies, it generates a variety of aerodynamic effects, most notably the vortices that are produced at the wingtips due to the pressure differential between the upper and lower surfaces of the wings. These vortices can persist for some time after the aircraft has passed and can pose significant hazards to following aircraft, particularly smaller ones that may be affected by the powerful and swirling air patterns left behind.

The other options describe different phenomena: enhanced airflow over the wing relates to aerodynamic lift, airborne moisture pertains to weather conditions affecting visibility, and drag due to fuselage design refers to resistance created by the aircraft’s shape. None of these directly address the specific implications and characteristics of the turbulence generated by an aircraft in flight, making the first option the most accurate representation of what wake turbulence is.