Final answer:
Option (a), Habitat destruction and pollution are two major ways the 'march of civilization' threatens rare wild animals, with deforestation and chemical pollutants causing direct harm.
Step-by-step explanation:
The 'march of civilization' threatens to bring about the extinction of certain rare wild animals through various means. Two significant ways are habitat destruction and pollution. Habitat destruction, which includes deforestation, damming of rivers, and urban development, directly impacts the natural environments that wildlife need to survive. Meanwhile, pollution from chemical runoff, plastic waste, and other pollutants can degrade the quality of habitats and poison animals directly.
Furthermore, the pet trade contributes to species extinction risks through mechanisms such as overharvesting and the introduction of exotic species. Overharvesting refers to the unsustainable collection of wildlife, either for use as pets or for parts. The introduction of exotic species into non-native ecosystems can disrupt local biodiversity and lead to native species decline through competition, predation, or disease.