What does an excessive angle of incidence on one wing lead to?

An excessive angle of incidence on one wing leads to unbalanced flight characteristics because it changes the lift distribution between the wings. When one wing is set at a greater angle, it generates more lift compared to the other wing. This difference in lift can cause the aircraft to roll toward the wing with the higher angle of incidence, leading to uncoordinated flight and difficulty in maintaining level flight. This condition requires the pilot to apply corrective measures to maintain control, which highlights how crucial balanced wing load is for stable flight performance.

As for the other options, while they might suggest some effects of altered aerodynamics, they do not accurately capture the critical issue that arises specifically from having one wing at an excessively high angle of incidence. For instance, excessive lift can lead to a stall, and improved climb rate is not necessarily guaranteed. Similarly, increased drag may result from altering the angle, but the primary concern in the context of this situation is the imbalance caused in aircraft handling.