Which of the following is true of the two symptom clusters of ADHD has two symptom clusters (hyperactive-impulsive and inattentive)?
a. Hyperactive symptoms are always more severe than inattentive symptoms.
b. Children commonly have symptoms from each cluster.
c. Symptoms from one cluster always predominate clearly in cases of ADHD.
d. Hyperactive symptoms persist longer over the lifespan than do inattentive symptoms