It's a stage of the very important Nitrogen cycle. All living things need Nitrogen, without it there is no life.
Answer:
Economic growth is directly related to environmental protection. Power plants and motor vehicles come with air pollution control technologies that someone makes and sells.
The correct answer is letter A. Biosphere is not directly studied in one of the main branches of Earth/Space science. This is a branch of science that focuses on living organisms that are living in different populations or communities all over Earth. The other three choices directly study these branches of Sciences.
