Improving air quality using command and control methods means $\_\_\_\_\_\_\_\_\_\_\_\_.$

following regulations that set an upper allowable limit of pollution release, which is enforced with fines and$/$or incarceration

paying a tax to the government on environmentally undesirable activities or enjoying a reduction in the tax in exchange for some desirable action

building tall smokestacks to send emissions high into the atmosphere so that they disperse and do not pool at the site of production

using free government money or resources intended to promote desired activities

following regulations that set upper limits for pollution release based on which producers are issued permits that allow them to release a portion of that amount; if they release less, they can sell their remaining allotment to others who did not reduce their emissions enough