Option (C) is correct because the textbook context clearly highlights that environmental degradation caused by human activities has become pervasive and dangerous. The text mentions several critical issues: the potential depletion of Earth's resources due to rapidly growing world population, natural forests being cut down leading to loss of biodiversity, the ozone hole posing real danger to ecosystems and human health, and coastal waters becoming increasingly polluted due to land-based activities. The context also notes that 663 million people lack access to safe water and 2.4 billion have no access to sanitation, resulting in millions of deaths. These examples demonstrate that environmental degradation has reached a dangerous level, which explains the growing concerns. Options (A) and (B) are partially true but do not capture the primary reason as comprehensively as Option (C) does.