A 2-month-old infant is brought to the pediatric clinic by anxious parents who report yellowish, greasy patches on the scalp that appeared at 4 weeks of age. The child is otherwise healthy, feeding well, and shows no signs of pruritus or systemic illness. On examination, the structure marked **A** in the diagram—greasy yellow scales in sebum-rich areas—is noted on the vertex and behind the ears. The parents ask about the prognosis and whether treatment is necessary. Which of the following statements best reflects the natural history and management approach for this condition?