Carbon dioxide from living things is also returned to teh atmosphere through processes of of dead tissue OA decomposition
OB combustion
OC photosynthesis
OD respiration

decomposition

Explanation:

the rotting smell is mixed with Co2

carbon dioxide from living beings is also returned to the atmosphere through processes of respiration of dead tissue.

The answer is (c) respiration

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."

the answer you are looking for is the united states forest service.

hope this !