which is the central element for all living things?\ncarbon\nhydrogen\noxygen\nnitrogen

Brief Explanations:

Carbon is the central element for all living things as it forms the backbone of organic compounds essential for life - such as carbohydrates, proteins, lipids, and nucleic acids. It can form stable covalent bonds with other carbon atoms and a variety of other elements, allowing for the vast complexity of biological molecules.

Answer:

carbon