Answer:
All of the options are correct.
Explanation:
In ecology, competition can be described as a fight between two organisms for limited resources like water, food shelter etc. Competition might occur in organisms from different species or it might occur in organisms of the same population.
Let's consider an area where the population of females is lesser as compared to males. In this area, the males will compete for mating with the females.
If there is limited space, birds of an area will compete for nesting sites.
In an area where the population is more than the carrying capacity, the organisms will compete for food.
