Which of the following describes a compound? (Hint: Carbon and Oxygen both appear on the periodic table.)
A. a piece of pure carbon, containing only carbon atoms.
B. oxygen gas surrounding a solid piece of carbon.
C. a substance made of two oxygen atoms for each carbon atom.
D. Carbon and Oxygen atoms mixed without being bonded together.
PLEASE HELP ME ASAP WKSNSNSNXSNDSNDSJ