Researchers believe that there is growing evidence to support the hypothesis that attention deficit hyperactivity disorder (ADHD) should not be dismissed as ordinary bad behaviour but should be recognized as a serious childhood disease. It is claimed that as many as one in five children are at risk of suffering this condition, which is linked to an increased risk of serious illness in adulthood. The disease is not caused by bad parenting, but a chaotic or difficult home environment in a childs early years acti- vates the syndrome where there already exists a genetic predisposition. If left untreated, sufferers were found to be four times more likely to suffer from mental illness as young adults.

Question: It can be inferred from the passage that as many as one in five young children suffer a chaotic or difficult home environment.
Options:
A. true, B. false, C. uncertain
Answer: "B"