Select a primary factor that leads to a low flare landing error.

Rounding out too high during the flare is a primary factor leading to a low flare landing error because it affects the aircraft's altitude and descent rate as it approaches the runway. When a pilot initiates the roundout too high, the aircraft may not transition smoothly to the landing attitude, resulting in a higher-than-desired descent rate. This can lead to a situation where the aircraft is unable to adequately slow its descent before touchdown, causing it to land too hard or even bounce. Optimal flare height is critical; it allows for controlled descent and a gentle touchdown. Misjudging the flare height negatively influences the entire landing process, potentially leading to problems such as nosing over or landing on the nose gear first.

In contrast, the other options address issues such as speed management or approach angle, which can also influence landing performance but don’t directly relate to the specific error of rounding out too high during the flare.