Final answer:
In case of cyanosis in an infant with tetralogy of Fallot, the correct option for positioning the infant is c) Hold the baby in a knee-chest position, which helps to alleviate the episode by increasing vascular resistance and reducing desaturation of blood.
Step-by-step explanation:
The question addresses how to care for an infant with tetralogy of Fallot, a congenital heart defect, when they exhibit cyanosis, which is the blue or purple coloration of the skin due to insufficient oxygenation.
The correct way to position the infant in this scenario, as per the nurse's instruction, is to hold the baby in a knee-chest position. This position helps to increase vascular resistance and decrease the return of desaturated blood to the body, potentially alleviating the cyanotic episode.
Therefore, the father demonstrates understanding of the nurse's instructions when he states that if the baby turns blue, he will hold the baby in a knee-chest position. This is option c) and is the correct option to choose when responding to cyanosis in an infant with tetralogy of Fallot.