Answer: A). Carbon atoms form the backbones of the organic molecules in living things.
Explanation: Carbon atoms forms the backbones of all organic molecules. The organic molecules found in living things include carbohydrates, lipids, proteins and nuclei acids. The building blocks of carbohydrates are monosaccharide sugars which have carbon backbones. The building blocks of proteins are amino acids, the building blocks of lipids are fatty acids while the building blocks of nucleic acids are nucleotides. The building blocks of all the biological molecules have carbon backbones. In these organic molecules, carbon atoms form the skeleton while atoms of other elements are attached to the carbon skeleton through different chemical bonds.