B. are more difficult to control than point sources. This is because A. is wrong (point source), and C. is wrong, because it doesn't necessarily cost less or more to identify the sources. D. may be right, as non point sources are natural, such as snow melts or rain.
Answer:
Las teorías extraterrestres o de panspermia sugieren que la vida existió en el espacio exterior y fue transportada por meteoritos, asteroides o cometas a una Tierra receptiva. En este caso, el origen de la vida no está relacionado con los posibles entornos de la Tierra primitiva.
Explanation:
I think they are all biotic factors..hmm if not take out whichever sounds the most not fitting.
Phosphorus is most commonly found in rock formations and ocean sediments as phosphate salts. Phosphate salts that are released from rocks through weathering usually dissolve in soil water and will be absorbed by plants. ... Animals absorb phosphates by eating plants or plant-eating animals.
