Correct Answer: B

Rationale: The correct answer is B. Most umbilical hernias in newborns resolve on their own by 3 to 5 years of age without the need for surgical intervention, unless complications arise. Surgery is not typically recommended for umbilical hernias in newborns due to the high rate of spontaneous resolution. Aggressive treatment is not necessary as umbilical hernias are typically benign and not associated with high mortality. Taping the abdomen is not recommended as it can cause skin irritation and does not speed up the resolution of the hernia.

Correct Answer: D

Rationale: Sweating is indeed one of the earliest signs of hypoglycemia in children with Type 1 diabetes. When blood sugar levels drop too low, the body releases stress hormones like adrenaline, which can lead to sweating. While irritability, rapid heartbeat, and confusion can also be seen in hypoglycemia, sweating is particularly common as a quick indicator of low blood sugar levels in children with Type 1 diabetes.

Correct Answer: A

Rationale: The Ortolani sign is a specific maneuver used during physical examination to detect hip instability or dislocation in infants. A positive Ortolani sign, where the hip is felt to slip back into the socket, is indicative of developmental dysplasia of the hip, a condition that can lead to long-term disability if not treated early. Romberg sign is used to assess sensory ataxia, Trendelenburg sign indicates weakness of the hip abductor muscles, and Gower's sign is seen in children with proximal muscle weakness climbing up their own body from a supine position due to conditions like muscular dystrophy.

Correct Answer: B

Rationale: The correct answer is B, Respiratory distress syndrome. Respiratory distress syndrome often presents with a "ground-glass" appearance on a chest x-ray in neonates due to surfactant deficiency. Choice A, Pneumonia, typically appears as patchy infiltrates on chest x-ray. Choice C, Bronchopulmonary dysplasia, is characterized by hyperinflation and fibrosis, not a ground-glass appearance. Choice D, Congenital diaphragmatic hernia, usually shows mediastinal shift and bowel loops in the chest cavity on x-ray, not a ground-glass appearance.

Correct Answer: B

Rationale: Melena indicates bleeding from the upper GI tract. The black, tarry appearance of the stool results from the partial digestion of blood as it passes through the intestines, typically originating from sources like the stomach or duodenum. Lower GI bleeding usually presents as bright red blood in the stool, originating from sources like the colon or rectum. Choices A, C, and D are incorrect because melena specifically points to upper GI bleeding rather than issues in the perianal/rectal area, lower GI tract, or hemorrhoids/anal fissures.