The correct answer to the question is option 2 - protection of the environment. "Silent Spring" is a highly influential book written by Rachel Carson. It is often regarded as one of the greatest science books ever published. The book primarily focuses on the protection of the environment.

Carson wrote "Silent Spring" in order to raise awareness about the harmful effects of pesticides, particularly DDT, on the environment and its inhabitants. She highlighted the negative impacts of these chemicals on plants, animals, and humans. The book played a significant role in sparking the modern environmental movement and led to the establishment of the Environmental Protection Agency in the United States.

While options 1 and 3 (wildlife preservation and pollution of the water body) are related to environmental concerns, they do not encompass the broader subject matter of "Silent Spring." The book addresses the larger issue of protecting the environment as a whole and the interconnectedness of various ecosystems. Therefore, option 2 is the most accurate choice.

Note: The provided answer is correct.