Nitrogen Fixation: Root and Bacteria Interactions. Nitrogen is an important macronutrient because it is part of nucleic acids and proteins. ... The most important source of BNF is the symbiotic interaction between soil bacteria and legume plants, including many crops important to humans.
Answer:
CH4
Explanation:
Combining hydrogen and carbon produces a group of organic compounds called hydrocarbons. Depending on the specific molecular formula, there can be many different types of hydrocarbons, such as the fuels propane and octane. The simplest hydrocarbon is methane, which has the chemical formula CH4.
A. Carbon
It's carbon because it is in all plants and fossil fuels. Hope this helps and is correct.