Answer:
Water should be the answer.
Primary producers use an energy source (usually sunlight) to build organic molecules.
Https://www.ncbi.nlm.nih.gov/pubmed/8300084
This might help
B. The levels of classification increased. Previously there were only 2 domains of life, Bacteria and Eukarya, but an additional domain and Kingdom were added when the distinction of Archaea was observed.
Quaternary or fourth order consumers are those who occupy the fourth position in the trophic level or food chain, that is, they are species or organisms that feed on tertiary consumers
