The most accurate response to how wildfire could immediately impact competition in a forest ecosystem is:
Competition would decrease. Wildfire would decrease the number of individuals competing for resources, making more resources available per individual.
Immediately after a wildfire, many plants and animals may be killed or displaced, which reduces the overall population density. This decrease in individual numbers can lead to reduced competition for the remaining resources, at least in the short term, as there are fewer individuals competing for the same amount of resources.