All the individuals of one type of clownfish living in a reef compose which level of organization

All the individuals of one type of clownfish living in a reef compose: a population.

Explanation:

A population can be defined as a group of individuals belonging to the same species that live in one area. Let's break down the information given in the question. The area is the reef. The individuals are the fish living in the reef, and they all belong to a species, clownfish. Thus, this scenario composes a population. Just to make the distinction clearer, if we included individuals of other species (other types of fish, for instance), we would have more populations in the same area and, in this case, we would be describing a community. However, since we are talking only of one species, it is a population.

first, the romans stayed isolated because they had to defend their own territories from neighboring cities that were harassing them, like the etruscans. second, once the romans managed to defeat their neighbors, and started to expand their territory, they started to build roads and bridges. finally, now that the romans have covered their territory with roads functioning as highways, they could mobilize their legions faster to assemble larger military units in a specific place.

sumerians were polytheistic, meaning they believed in many different gods. so, the best answer is c.