Final answer:
The building blocks of carbon compounds are monomers, like amino acids and nucleotides, which are the basic units of proteins and nucleic acids, respectively.
Step-by-step explanation:
The building blocks of carbon compounds vary depending on the type of compound in question. For example, amino acids are the monomers of proteins, each consisting of a central carbon atom bonded to an amino group (-NH₂), a carboxyl group (-COOH), a hydrogen atom, and a variable R group. On the other hand, nucleotides are composed of one or more phosphate groups, a pentose sugar, and a nitrogen-containing base, and they are the building blocks of nucleic acids such as DNA and RNA. In this context, the correct answer to the student's question would be 'C) Monomers,' as monomers are the general term for the single molecules like amino acids or nucleotides that can bind together to form polymers in carbon compounds.