A 7-month-old infant is brought to the clinic for a 2-month history of an intensely pruritic rash. The parents report the infant scratches frequently and has trouble sleeping. Examination shows erythematous papules and plaques with overlying excoriations and lichenification on the cheeks and symmetric patches on the elbows and knees. There are no honey-colored crusts. Family history is significant for asthma in the father. Which of the following body-surface distributions is most characteristic of this child’s condition at this age?