Which of the following studies would a community ecologist undertake to learn about competitive interactions?
a) selectivity of nest sites among cavity-nesting songbirds
b) the grass species preferred by grazing pronghorn antelope and bison
c) nitrate and phosphate uptake by various hardwood forest tree species
d) stomach analysis of brown trout and brook trout in streams where they coexist
e) selectivity of nest sites among cavity-nesting songbirds, the grass species preferred by grazing pronghorn antelope and bison, nitrate and phosphate uptake by various hardwood forest tree species, and stomach analysis of brown trout and brook trout in streams where they coexist

        The right answer to this question is option E) selectivity of nest sites among cavity-nesting songbirds, the grass species preferred by grazing pronghorn antelope and bison, nitrate and phosphate uptake by various hardwood forest tree species, and stomach analysis of brown trout and brook trout in streams where they coexist

Explanation:

        Competitive interactions are based in a really simple context, organisms interacting with themvelves fighting for the same source of energy to survive. In that way, be careful, the organisms don't need to be the same, only the source of energy. For example: a bear likes to eat red fish at a certain river, but, wild cats like to eat red fish at the same river too, in that way, they are having a competitive interaction for the same source of energy. In the case of the trout, it's the same, they're competing against another species of trout to get their food.