How can turbulence affect an aircraft?

Turbulence is primarily caused by various atmospheric conditions that result in irregular air movement, which can lead to sudden changes in altitude or flight path. This means that when an aircraft encounters turbulence, it may experience rapid variations in altitude, which can make passengers and crew feel a sensation of being lifted or dropped.

The correct choice emphasizes the unpredictability of turbulence, as it can cause abrupt changes that affect an aircraft's flight dynamics. Pilots and crew are trained to manage these conditions, but understanding that turbulence can lead to sudden drops or changes in altitude is crucial for both safety and comfort during a flight. This knowledge aids in reinforcing the importance of seatbelt use and adherence to safety protocols during such conditions.

In contrast, other options reflect misconceptions about turbulence. For instance, turbulence does not only cause an aircraft to ascend or affect only small aircraft, nor is it true that turbulence has no impact on flight safety. All aircraft, regardless of size, can encounter turbulence, and safety measures are in place to address its effects.