Final answer:
ADHD is a neurodevelopmental disorder characterized by symptoms of inattention, impulsivity, and hyperactivity. It does not necessarily have to be present prior to the age of 3, but can persist into adulthood. In addition, children with ADHD are at an increased risk for injury due to impulsivity and difficulty controlling behavior.
Step-by-step explanation:
ADHD, or attention deficit/hyperactivity disorder, is a neurodevelopmental disorder that affects approximately three to five percent of children and adults. It is characterized by symptoms such as inattention, impulsivity, and hyperactivity. Contrary to option A, behaviors associated with ADHD can be present after the age of 3 and throughout childhood and adulthood. Option D is correct, as ADHD can result in an increased risk for injury due to impulsivity and difficulty controlling behavior. Options B and C are not accurate statements about ADHD. It is important for the nurse to provide correct information and support to the parent of a child with ADHD.