Which of the following statements regarding patients with sickle cell anemia is TRUE?
(A) Acute chest syndrome is the leading cause of death from sickle cell disease in the United States.
(B) Hydroxyurea effectively decreases the frequency and severity of painful crises in children.
(C) Infants often present at around 3 months of age with dactylitis (hand-foot syndrome).
(D) Simple or exchange transfusion is indicated for dactylitis.