A hydrocarbon is said to be saturated if:
                A)           one end of the molecule is hydrophilic while the other end is hydrophobic.
                B)            it has one or more double bonds between carbon atoms.
                C)            it contains more than one functional group.
                D)           each internal carbon atom is covalently bonded to two hydrogen atoms.
                E)            its functional groups include at least one aromatic ring.