Please help asap timed test will decide if I fail

Plz ! ive been stuck on this forever

Dna replication or repair occurs in a cell in all of thw following situations except when

The double bond between a carbon atom and two oxygen atoms (a molecule of carbon dioxide) has two characteristics. what are they? a.an ionic bond is formed between the oxygen and carbon atoms. b.four valence electrons are shared. c.two valence electrons are shared. d.valence electrons are shared between oxygen atoms.