What method is commonly used to ventilate a structure during a fire?

The method of ventilating a structure during a fire involves multiple techniques that can effectively reduce heat, smoke, and toxic gases, thereby improving visibility and conditions for firefighters as they work to suppress the fire.

Cutting holes in the roof is one of the most common methods employed by firefighters. This process, known as vertical ventilation, allows hot gases and smoke to escape from the upper levels of the structure. It creates an opening that improves the efficiency of the firefighting efforts by allowing cooler air to enter through lower openings and enhancing the overall flow of air within the structure.

Opening windows also serves as an effective ventilation method. By doing so, it can help release heat and smoke from the interior, lowering the likelihood of backdraft phenomena and aiding in the removal of hazardous gases.

Using exhaust fans is another technique to facilitate ventilation. These fans can mechanically push out smoke and heat, especially in scenarios where natural ventilation methods may be insufficient due to the complexity of the structure or the intensity of the fire.

In summary, the collective use of cutting holes in roofs, opening windows, and employing exhaust fans represents a comprehensive approach to ventilation during firefighting operations, making "All of the above" the correct and most inclusive answer.