Correct Answer: B

Rationale: The correct answer is B: Clubbing of fingers. Clubbing of fingers is a common manifestation in children with tetralogy of Fallot due to chronic hypoxia. This condition causes the fingertips and nails to enlarge, creating a bulbous or club-like appearance. Slow respirations (Choice A) are not a typical clinical manifestation of tetralogy of Fallot. Decreased RBC counts (Choice C) may be seen in conditions like anemia but are not specific to tetralogy of Fallot. Subcutaneous hemorrhages (Choice D) are not a characteristic clinical manifestation of tetralogy of Fallot.

Correct Answer: D

Rationale: The most common treatment for Hirschsprung disease is the surgical removal of the affected section of the bowel. This procedure entails excising the part of the colon that lacks nerve cells crucial for normal bowel function. Daily enemas (Choice A) can offer temporary relief for constipation but do not address the root cause of the condition, which is the absence of nerve cells. A low-fiber diet (Choice B) is not a primary therapy for Hirschsprung disease and may not effectively manage the disorder. A permanent colostomy (Choice C) is typically considered in severe cases where other interventions have failed and is not the standard management approach for Hirschsprung disease.

Correct Answer: A

Rationale: The correct answer is A: 'It is a condition affecting the respiratory and digestive systems.' Cystic fibrosis is a genetic disorder that primarily affects the respiratory and digestive systems. It is caused by a defective gene that leads to the production of thick and sticky mucus in these organs. This mucus can clog airways in the lungs and block the ducts in the pancreas, affecting digestion. Choice B is incorrect because cystic fibrosis is not an autoimmune disorder; it is a genetic condition. Choice C is partially correct in that cystic fibrosis is a genetic disorder, but merely managing it with medication oversimplifies the comprehensive care needed for individuals with cystic fibrosis. Choice D is incorrect as cystic fibrosis is not caused by prenatal exposure to toxins but is a genetic condition inherited from parents.

Correct Answer: C

Rationale: Longer periods of sleep than usual can be a sign of illness in infants. When an infant sleeps more than usual, it may indicate that the baby is conserving energy due to an underlying condition. Grunting respirations (choice A) can be a sign of respiratory distress, excessive perspiration (choice B) may indicate overheating or fever, and crying immediately after feedings (choice D) can be a sign of gastrointestinal discomfort, such as colic or reflux. However, in this scenario, the emphasis is on changes in sleep patterns as a potential indicator of illness.

Correct Answer: C

Rationale: Positive fibrin split products indicate disseminated intravascular coagulation (DIC), a condition characterized by the widespread formation of blood clots throughout the body. In DIC, clotting factors are consumed, leading to increased fibrin split products. A shortened prothrombin time (Choice A) is not typically seen in DIC as it indicates faster blood clotting, which is not consistent with the pathophysiology of DIC. An increased fibrinogen level (Choice B) is also not a characteristic finding in DIC, as fibrinogen levels may be decreased due to consumption in the formation of clots. Increased platelets (Choice D) are not typically observed in DIC; instead, thrombocytopenia (decreased platelet count) is more common due to their consumption in clot formation.