What action should be taken to prevent ice formation on aircraft surfaces effectively?

Using anti-ice fluid during cold conditions is an effective measure to prevent ice formation on aircraft surfaces. Anti-ice fluids are specially formulated to lower the freezing point of moisture that may accumulate on the aircraft, thereby preventing ice from forming on critical surfaces such as wings and tail. These fluids can help maintain the aircraft's aerodynamic properties and control effectiveness, which is crucial during flight and landing.

In contrast, reducing engine power before landing does not directly address ice formation and could compromise engine performance, especially in cold weather. Increasing landing gear deployment speed is unrelated to the prevention of ice accumulation on the airframe and could lead to other aerodynamic concerns. Turning off all cabin heating systems could lead to further icing concerns, as cabin heat helps manage temperature differences that can affect moisture accumulation on the aircraft surfaces. Using anti-ice fluid is the targeted and effective approach to mitigate ice-related hazards in aviation.