<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 4-day-old male infant is brought to the physician because of respiratory distress and bluish discoloration of his lips and tongue. He was born at term and the antenatal period was uncomplicated. His temperature is 37.3C 99.1F, pulse is 170min, respirations are 65min, and blood pressure is 7046 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 82. A grade 36 holosystolic murmur is heard over the left lower sternal border. A single S2 that does not split with respiration is present. Echocardiography shows defects in the interatrial and interventricular septae, as well as an imperforate muscular septum between the right atrium and right ventricle. Further evaluation of this patient is most likely to show which of the following?? A: Increased pulmonary vascular markings on chest x-ray, B: Tracheal bowing on chest x-ray, C: Left-axis deviation on electrocardiogram, D: Elfin facies, E: Delta wave on electrocardiogram,  <response>: This is a patient with cyanosis and respiratory distress in the newborn period. The description of the heart murmur, single S2, and echocardiogram findings are consistent with tetralogy of Fallot, which classically consists of a ventricular septal defect, overriding aorta, right ventricular outflow tract obstruction, and right ventricular hypertrophy. The question asks what would likely be seen on further evaluation of this patient. Choice A of increased pulmonary vascular markings would not be expected, since the right ventricular outflow tract obstruction limits pulmonary blood flow, leading to decreased, not increased, pulmonary vascularity. Choice B of tracheal bowing suggests compression of the trachea and is more consistent with vascular rings, not tetralogy of Fallot. Choice C of left axis deviation on ECG is common in tetralogy of Fallot due to right ventricular hypertrophy. This is the most likely finding.Choice D of elfin facies is a dysmorphic facial feature seen in some genetic syndromes but not specifically expected in tetralogy of Fallot. Choice E of delta wave on ECG is seen in pre-excitation syndromes like WPW, not in tetralogy of Fallot.In summary, the left axis deviation on ECG in choice C is the most likely finding in this patient with tetralogy of Fallot.C: Left-axis deviation on electrocardiogram 