Correct Answer: C

Rationale: The correct answer is C: Osgood-Schlatter disease. This condition is a common overuse injury that affects the knee. Osgood-Schlatter disease typically occurs in children and adolescents who are involved in activities that require frequent running, jumping, and kicking. It is characterized by pain, swelling, and tenderness at the tibial tuberosity, where the patellar tendon inserts into the tibia. Choice A, Dislocated radial head, is not an overuse disorder but rather a form of elbow injury where the head of the radius bone is displaced from its normal position. Choice B, Transient synovitis of the hip, is a self-limiting condition that causes hip pain and limping in children. It is not typically considered an overuse disorder. Choice D, Scoliosis, is a condition characterized by an abnormal lateral curvature of the spine. While it may be related to certain activities or postures, it is not primarily classified as an overuse disorder.

Correct Answer: A

Rationale: Infection is the most common cause of shock in infants and children due to their increased susceptibility to sepsis. Infants and children have underdeveloped immune systems, making them more prone to infections that can lead to septic shock. While cardiac failure is a serious condition, it is not the most common cause of shock in this population. Accidental poisoning, though dangerous, is less common than infection in causing shock in infants and children. Severe allergic reactions can lead to anaphylactic shock, but they are not as prevalent as infections in causing shock in this age group.

Correct Answer: B

Rationale: The correct answer is B. Myelination occurs in a cephalocaudal (head-to-toe) pattern, improving nerve function progressively. Choice A is incorrect because myelination continues beyond 4 years of age and into adolescence. Choice C is incorrect as myelination speeds up nerve impulses rather than slowing them down. Choice D is incorrect because myelination increases the specificity and efficiency of nerve impulses, making them more focused and precise.

Correct Answer: C

Rationale: The correct answer is C. Longer periods of sleep than usual can be a sign of illness in infants. When an infant sleeps more than usual, it can indicate that the baby is conserving energy due to an underlying condition. Grunting respirations (choice A) can be a sign of respiratory distress, not just an indication of illness. Excessive perspiration (choice B) can occur due to various reasons and is not a specific major indication of illness. Crying immediately after feedings (choice D) is a common behavior in infants and not necessarily a major indication of illness.

Correct Answer: A

Rationale: Right lower quadrant pain is a characteristic clinical manifestation of appendicitis. The appendix is typically located in the right lower quadrant of the abdomen, so pain in this area is a common symptom. Left lower quadrant pain (Choice B) is less likely in cases of appendicitis. Rebound tenderness (Choice C) is a sign of peritonitis, not specific to appendicitis. Epigastric pain (Choice D) is more indicative of upper gastrointestinal issues rather than appendicitis.