What factors contribute to extreme fire behavior?

Extreme fire behavior is primarily influenced by environmental conditions that promote the rapid spread and intensity of wildfires. The correct choice highlights the critical combination of high winds, low humidity, and high temperatures, along with the presence of dry fuels.

High winds can carry sparks and embers, allowing fires to jump ahead of themselves and spread rapidly over large distances. Low humidity reduces moisture content in both the air and available fuels, making them more susceptible to ignition. High temperatures increase the likelihood of ignition and can intensify fire behavior by promoting combustion further.

When these factors are present, they create an environment conducive to extreme fire behavior, leading to rapid growth and development of fires that can be challenging to control.

In contrast, the other options present scenarios that do not support extreme fire conditions. For instance, high moisture and wet fuels contribute to fire suppression rather than enhancement. Calm winds and high humidity create a stable environment that typically results in less vigorous fire activity. Finally, minimal vegetation would limit available fuels and therefore diminish the overall fire intensity and spread.