None of these sound like a star, but the closest one would have to be B in my opinion.
Answer: The transfer of the minerals of the earth to living organisms and then back to the earth again is called a cycle
Answer:
Population growth (or decline) is influenced by many factors that fall into the broad realms of demographic characteristics, socioeconomic conditions, transportation infrastructure, natural amenities, and land use and development across space and time.
Answer:
It is a transportation barrier