The use of seat belts in cars has significantly reduced the number of crash fatalities. Which statement best explains how the market forces of supply and demand guided the development of seat-belt technology? A. When a large enough supply of seat-belt parts became available, the public demand for their use in cars increased.B. Consumers' desire for more comfortable seat belts led engineers to improve seat belts.C. Engineers recognized the dangers of not wearing a seat belt and decided to develop systems that would be affordable to manufacture.D. As car manufacturers developed seat-belt technology, they began to advertise seat belts' ability to prevent injuries and death to consumers.