Which part of the passage is the extension? A. Mounds of scrap tires are also breeding grounds for other health
hazards because the tires provide a shelter for rodents, snakes,
and insects.
B. Trashed tires are becoming a problem in the United States.
C. Many areas have become unauthorized dump sites, which not
only harms the environment, but also causes health risks for
those who live near these tire wastelands.
D. When tires burn, the fire continues for days and weeks at a time,
releasing toxic chemicals into the air.