About fifty years ago, the EPA, Environmental Protection Agency, embraced command and control laws. Later on, the EPA made adjustments and updates. These laws and their adjustments,

A/draws distinctions between the needs of firms and costly equipment upgrades.

B/are given considerable credit for cleaner air and water in recent decades.

C/ were an inexpensive incentive for industrial polluters to improve performance.

D/ were necessary as US industries had zero incentive to control pollution.