The mean age range for breast bud appearance (thelarche) in females is

Correct Answer: D

Rationale: Thelarche typically occurs between ages 8-13, marking the start of female puberty.

Correct Answer: B

Rationale: Medullary relapse, or recurrence of leukemia in the bone marrow, is the most common form of relapse in acute leukemia, requiring additional chemotherapy.

Correct Answer: C

Rationale: Congenital pneumonia with sepsis is likely given the low WBC count, prematurity, and need for ventilation

Correct Answer: B

Rationale: Intubation is indicated in neonates when there is inadequate oxygenation despite supplemental oxygen, as it may be necessary to provide more effective ventilation and support for gas exchange.

Correct Answer: B

Rationale: Von Willebrand disease causes prolonged bleeding time despite normal platelet count due to defective platelet adhesion from a deficiency in von Willebrand factor.