Answer:
A. social welfare will be enhanced when some, but not all air pollution is eliminated.
C. social welfare is optimal when all air pollution is eliminated.
Explanation:
A negative extenality depicts cost suffered by a third party as a result of an economic transaction. From the above social welfare will be promoted if air pollution is reduced since it only partly reduced pollution. Social welfare would only be optimal when all pollution has been eliminated. To enhance social welfare and reduce or ultimately eliminate pollution, government usually makes use of tax measures(on pollution producing factories).
