Read the Following Scenario and Answer the Question Below

Read the following scenario and answer the question below.
Thousands of young families moved ʺover the hillsʺ and into the San Fernando Valley, a suburb of Los Angeles, after World War II. New neighborhoods were springing up, replacing orange groves and open space; roads and schools quickly sprang into existence, trying to keep pace with the rapid population growth. Ringed by beautiful mountains, the entire Los Angeles basin looked like a new, green, sun-filled paradise to the families seeking a fresh start. In the early 1950s, one of the common family chores in Los Angeles was to carry the trash out to the stone incinerator behind the garage where each family burned all of their dry trash. ʺWetʺ garbage was collected and taken to a city dump, where it was burned by the city. Everyone throughout the city either used an incinerator or burned things in an open trash pile; there were over 400,000 backyard trash incinerators. On warm afternoons, eyes would sometimes sting and burn. People would stop, close their eyes, and let the cleansing tears refresh irritated eyes. They accepted this as a normal part of life in sunny California.
-In 1958 trash collection programs were established, and backyard incinerators were banned in the hope of reducing smog. However, it was estimated that massive amounts of gasoline were evaporating from storage tanks, fuel pump nozzles, and delivery trucks. This was also considered a serious contributor to smog, and over the next 20 years several new rules, and several new devices, were put in place to alleviate it. There was still a great deal of smog, now identified as photochemical smog, despite the changes. The major remaining problem was _________________

A) too many coal-fired power plants along the coast
B) insufficient city funding to improve waste dumps
C) the large distances traveled daily by solitary commuters
D) indoor pollution from new houses, with new furniture
E) the influx of new manufacturing, with new chemicals