The answer is; B
The carbon cycle exists in the atmosphere mainly as carbon dioxide. The levels of carbon dioxide change can change dramatically over years. The movement in and out of carbon in the atmosphere is fast and influences by factors such as combustion and photosynthesis. The former increases carbon in the atmosphere whole the latter decreases it.
Peer review other scientist will check the findings before it gets published
Skin is a barrier that serves as one of the body's first lines of defense against harmful microbes. Specialized immune cells within skin tissue help to fight invading organisms. Past work by an NIH research team showed that commensals can help the body's immune cells fight disease-causing microbes.
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