Which substance(s) could be formed during the incomplete combustion of a hydrocarbon?

Question

I. Carbon

II. Hydrogen

III. Carbon monoxide

A. I only

B. I and II only

C. I and III only

D. II and III only

Answer 1

i would go with C or D

Answer 2

B

Answer 3

hydrocarbons in the purest form is carbon atoms bonded to one and other with the remaining free electrons bonded to hydrogen atoms. In combustion you add heat and oxygen (O2) and the only possible outcome is CO and H+. The only other possibilitiess are from impurities.

So the answer is "D"