Combustion of gasoline in automobile engines produces benzene, a known carcinogen. Environmentalists propose replacing gasoline with methanol, which does not produce significant quantities of benzene when burned. However, combustion of methanol produces formaldehyde, also a known carcinogen. Ttherefore the environmentalists' proposal has little merit. Which one of the following, if true, most supports the environmentalists' proposal? ['The engines of some automobiles now on the road burn diesel fuel rather than gasoline.', 'Several large research efforts are underway to formulate cleaner-burning types of gasoline.', 'Formaldehyde is a less potent carcinogen than benzene.', 'Since methanol is water soluble, methanol spills are more damaging to the environment than gasoline spills.']