<span>because the molcules are formed................................... have a nice day
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Answer: Commensalism
Explanation: Well you can already eliminate parasitism because that is when an organism leeches off another. Mutualism is when one organism needs to depend on another compared to A where both are benefited. Then you can eliminate d because competition is when two organism compete with each other for survival not benefiting them both.
A molecule is made of more than one atom of differing elements that can be simplified while an element cannot be simplified because it is only one atom of one type of element.