Option 1 -> The passage states fizzy drinks substitute milk, causing children to miss calcium and vitamin D, leading to brittle bones, not strong density.
Option 2 -> The passage mentions sedentary lifestyle prevents children from getting "bone-building benefits of vigorous exercise," meaning it weakens bones.
Option 3 -> The passage explicitly states "Osteoporosis isn't just your grandmother's health threat" and mentions children can be diagnosed at an earlier age.
Option 4 -> The passage clearly states "Osteoporosis can be fatal: up to 25 percent of older people who suffer a broken hip die within a year."
Hence, Option 4: Osteoporosis can be life-threatening -> The passage directly mentions that osteoporosis can be fatal, with up to 25% of older people dying within a year of suffering a broken hip, making it a life-threatening condition -> correct