A nurse is assisting in the care of an infant diagnosed with tetralogy of Fallot. The mother asks the nurse to explain the condition. Which of the following statements should the nurse include in the explanation?

Choice A reason: Tetralogy of Fallot causes reduced pulmonary blood flow due to pulmonic stenosis, not increased flow. This leads to cyanosis from right-to-left shunting, making this incorrect, as it misrepresents the pathophysiology, requiring the nurse to clarify the condition’s impact on circulation. Choice B reason: Tetralogy of Fallot involves four defects (ventricular septal defect, pulmonic stenosis, right ventricular hypertrophy, overriding aorta), causing oxygen-poor blood to circulate due to right-to-left shunting. This is the correct explanation, accurately describing the condition’s impact on oxygenation for the mother. Choice C reason: Narrowing of the aortic valve describes aortic stenosis, not tetralogy of Fallot, which involves multiple defects, including pulmonic stenosis. This is incorrect, as it does not reflect the condition’s four defects or their effect on circulating oxygen-poor blood. Choice D reason: Tetralogy of Fallot involves four defects, not a single defect, and causes partial mixing of blood due to shunting, not complete mixing. This is incorrect, as it oversimplifies the condition, requiring the nurse to explain the four defects causing cyanosis.