What do ailerons, flaps/slats, and spoilers/speed brakes do?

• A. Ailerons control roll; flaps/slats improve takeoff/landing performance; spoilers/speed brakes increase drag and decrease lift.
• B. Ailerons control pitch; flaps/slats control yaw; spoilers increase lift.
• C. Flaps/slats control roll; ailerons increase drag; spoilers provide propulsion.
• D. Spoilers provide lift; flaps/slats provide thrust; ailerons provide yaw.

Answer: (A)

The main idea is how each flight surface changes the aircraft’s motion and performance. Ailerons are the primary roll controls—when one aileron rises and the other lowers, the wings generate different lift levels, tilting the aircraft and producing a roll for turns. Flaps and slats are high‑lift devices that increase wing camber and effective wing area at lower speeds, which boosts lift and lets the plane take off at shorter distances and land more slowly and steeple down with a safer approach. Spoilers and speed brakes disrupt the airflow over the wing to kill lift and create drag, helping slow the airplane down and shorten the descent or accelerate deceleration.

So this combination matches the roles: roll control, lift augmentation for takeoff/landing, and lift reduction with drag for descent or braking. Other options mix up surfaces—pitch or yaw control is not done by ailerons, yaw is by the rudder; flaps/slats don’t control yaw; spoilers don’t provide propulsion.