Which of these solutions is the best way to help a city as its population grows

and its air becomes more polluted?
A. Reduce air-quality regulations so businesses can grow
unimpeded.
B. Invest in alternative energy sources to reduce emissions.
C. Invest in urban sprawl to better disperse the pollution.
D. Reduce road construction to dissuade new residents.

B. Invest in alternative energy sources to reduce emissions.