Three organic compounds A, B and C have the following molecular formulae : A C4H8O2 B C4H10O C C4H8O (a) Which compound contains an alcohol group? Write its name and structural formula. (b) Which compound contains a carboxyl group? Write its name and structural formula. (c) Which molecular formula can represent an aldehyde as well as a ketone? Write the names and structural formulae of the aldehyde and ketone represented by this molecular formula.