Every year, nearly 1.2 million acres of land are burned in wildfires. Lightning and other natural occurrences cause some of these fires. However, humans cause 90 percent of wildfires. Cigarettes, campfires, equipment, and more can ignite fires that end up spreading due to dry leaves, needles, branches, and weather conditions. Wildfires can help the ecosystem when they are contained. But they can also damage an area, making it difficult for the land to heal on its own. Wildfires can also increase erosion and landslides. A. problem and solution B. cause and effect C. chronological order D. compare and contrast