Which airframe component helps control pitch?

The horizontal stabilizer is the correct component that helps control pitch in an aircraft. This part of the airframe is located at the tail and is crucial for maintaining stability in the vertical plane. The horizontal stabilizer works in conjunction with the elevator, which is located on its trailing edge.

When the pilot moves the control yoke or stick forward or backward, it deflects the elevator up or down, causing the nose of the aircraft to pitch up or down, respectively. This manipulation of the elevator changes the airflow around the horizontal stabilizer and affects the overall aerodynamic forces acting on the aircraft, allowing for controlled ascent and descent during flight.

The other components listed have different roles. The vertical stabilizer primarily influences yaw, helping to maintain directional stability. Ailerons are located on the wings and are responsible for roll, allowing for turns. The rudder, which is part of the vertical stabilizer, also contributes to controlling yaw rather than pitch. Thus, the horizontal stabilizer, along with its elevator, plays the primary role in controlling an aircraft's pitch.