In the 1960s and 1970s,___________

In the 1960s and 1970s,___________.

A) it became more difficult to demonstrate that a toxin from a particular source was responsible for harming life
B) federal legislators saw regulation as an impediment to economic growth
C) most environmental problems were addressed after the fact through litigation
D) oil release into coastal waters was first banned
E) environmental problems in one state started affecting other states more often