Environmentalist: It takes less energy to make molten glass from recycled glass than from raw materials. Once the recycled glass or raw materials have been turned into molten glass, making bottles from recycled glass follows the same process as making bottles from raw materials. Obviously, soft drink bottlers who make a large percentage of their bottles from recycled glass have significant energy savings. Ttherefore, by using recycled glass instead of glass made from raw materials, bottlers can lower their costs and benefit the environment at the same time. Which one of the following is an assumption on which the argument relies? ['Purchasing and transport costs are not so much greater for recycled glass than for raw materials that they outweigh the savings in energy costs resulting from the use of recycled glass.', 'The amount of glass that is currently recycled each year is enough to supply the major soft drink bottlers with materials for a large percentage of the glass bottles they make that year.', 'Most consumers are not able to distinguish bottles made from recycled glass from glass bottles made from raw materials.', 'The process of making molten glass from recycled glass requires fewer steps than does the process of making molten glass from raw materials.']