Answer: a. The national government instituted regulations to handle environmental issues.
The 1960s and 1970s were a period of increased awareness about environmental issues among the population. One of the catalysts was the book <em>Silent Spring</em> (1962) by Rachel Carson. The book discussed the negative effects of pesticides, in particular DDT, on wildlife. The 1969 Santa Barbara oil spill also generated public outrage. As a result, many regulations were passed in order to protect the environment. Moreover, those that already existed were reviewed and rewritten to make them more comprehensive.
