Answer:
D. nitrogen, carbon, hydrogen, oxygen, sulfur
Step-by-step explanation:
Proteins are giant organic molecules. The monomers that combines to form proteins are the amino-acids.
The atoms that makes up the amino-acids units of proteins are carbon, hydrogen, oxygen, Nitrogen and sometimes sulphur.
Not all amino acids contains sulfur in their structure.
These atoms are also the atoms that makes up proteins when they are broken down.