Which flight characteristic can be destabilized by a misaligned control surface?

A misaligned control surface can significantly impact yaw stability, which refers to an aircraft's ability to maintain its directional heading without uncommanded rolling or turning. When the rudder or other control surfaces responsible for yawing are not aligned correctly, the aircraft may experience asymmetric forces. This misalignment can lead to unintended yaw motion, requiring the pilot to make constant corrections, ultimately compromising the aircraft's stability and control during flight.

The other flight characteristics listed, such as altitude stability, speed control, and fuel consumption, are influenced more by other factors, including the overall aerodynamic design, engine performance, and flight management rather than the alignment of control surfaces specifically focused on yaw. Therefore, the primary impact of a misalignment in the context of this question relates to yaw stability.