a metal an atom a compound a nonreactive gas
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: The elements sulfur (S) and oxygen (O2) combine to form a substance called sulfur dioxide (SO2). Sulfur dioxide is also formed when coal and oil are burned. Sulfur dioxide can best be described as
Possibilities:
- a metal
- an atom
- a compound
- a nonreactive gas

a compound