【单选题】

Questions 14 and 17 are based are the following passage.At the end of the passage, you will be given 20 seconds to answer the questions.

Now listen to the passage.
Which solution is NOT mentioned to solve the pollutionA．To improve the public transport system.
B．To encourage people not to use private cars frequently.
C．To introduce emission controls on all cars.
D．To persuade factories to use less fossil fuels.