Rachel Carson's book "Silent Spring" (1962) is a pivotal work in environmental science and literature, raising awareness about the adverse environmental effects caused by the indiscriminate use of pesticides. The book meticulously documented how pesticides, especially DDT, were contaminating the environment and harming wildlife, particularly birds. Carson highlighted the interconnectedness of ecosystems and warned of a 'silent spring' where no bird songs would be heard due to their deaths caused by pesticide poisoning. Her work spurred an environmental movement, leading to policy changes and the eventual ban of DDT in many countries. Therefore, the correct answer is the adverse environmental effects caused by the indiscriminate use of pesticides.