In 1988, wildfires swept through nearly 800,000 acres of Yellowstone National Park. The fire killed many of the trees and shrubs, leaving vast swaths of land without plants. This left the burned area open for new plant colonization. Forest fires also tend to release large amounts of nutrients to the soil. Within a few years, some species of plants, such as fireweed, experienced exponential growth in the burned area. Which of the following environmental factors likely led to the exponential growth seen in fireweed after the Yellowstone wildfires?

a. Increase in habitat
b. Increase in nutrients
c. Decrease in competition from other plants
d. Increase in predation from insects
e. Increase in sunlight

The lost of many plant species including big trees that once completed with and surpressed the fireweed paved way for the thriving of this plant species.

The fireweed has enough space, abundant nutrient, exposure to sunlight which aided its exponential growth as a result of decrease in competition for these same resources from other plants which are now lost due to the wildfire that claimed many area of the park.