Competitive exclusion controls population size true or false

The given statement is correct.

According to competitive exclusion, two species competing for the same limiting resource ( like food) in a particular area can not exist together. The species having slight advantage over the other will survive and exclude the other one. By doing so, it controls the size of a population. The other species will either extinct or move to some other ecological niche.

Thus, competitive exclusion controls population size.

i think that c)gold was found there

but i am not sure

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link: