Answer: a flowering plant
A carbon film is an outline of a fossil. It is a kind of fossil that is seen on the undersurface of rocks. During fossilization, the soft body tissues are decomposed generally, while the hard tissues, such as bones and shells remain left. Soft tissues, like flowers and leaves are made up of organic compounds mainly. When these structures get buried, their carbon compounds compressed and leave the impressions as carbon film. Therefore, a flowering plant will develop as a residue or film of carbon most likely.