Correct Answer: B

Rationale: The correct answer is B: Within the first week of birth. Classical vitamin K deficiency bleeding typically occurs within the first week of birth due to low levels of vitamin K in newborns. During this time, infants are at a higher risk of bleeding complications if not supplemented with vitamin K. Choice A is incorrect because bleeding usually occurs after the first 24 hours. Choice C is incorrect as it does not specify a specific time frame within the neonatal stage. Choice D is incorrect as classical vitamin K deficiency bleeding is typically seen within the first week, not necessarily during the entire infancy stage.

Correct Answer: A

Rationale: The correct answer is A: Six hours postnatally. Cephalohematoma is a collection of blood between a baby's skull and the periosteum. It typically appears several hours after birth due to trauma during delivery, causing bleeding under the periosteum. This allows time for the blood to accumulate and form a distinct swelling, making the onset around six hours postnatally. Choices B, C, and D are incorrect as they do not align with the typical timeline for the development of cephalohematoma.

Correct Answer: A

Rationale: The correct answer is A because folic acid supplementation plays a crucial role in promoting spinal cord closure during fetal development, preventing neural tube defects. Folic acid helps in the formation of neural tube structures, ensuring proper closure and preventing defects like spina bifida. Choices B, C, and D are incorrect as preventing infections, enhancing fetal growth, and regulating blood sugar levels are not direct mechanisms through which folic acid prevents neural tube defects.

Correct Answer: D

Rationale: The correct answer is D: Check the neonate’s vital signs every 2-4 hourly. This is the priority action because neonates undergoing phototherapy are at risk for dehydration and temperature instability. Monitoring vital signs regularly helps to detect any signs of dehydration, such as decreased urine output or increased heart rate, and ensures timely intervention. Explanation for other choices: A: Turning the neonate every six hours routinely is important for preventing pressure ulcers but is not the priority when compared to monitoring vital signs for potential complications. B: Encouraging the mother to discontinue breastfeeding is incorrect as breastmilk provides essential nutrients and hydration, which are important for neonates, even during phototherapy. C: Notifying the physician if the skin turns bronze-colored is important to address a potential adverse reaction to phototherapy but does not take precedence over monitoring vital signs for immediate concerns.

Correct Answer: D

Rationale: The correct answer is D: A HIDA scan. A HIDA scan is the most appropriate imaging study for investigating the likely cause in this case because the patient's symptoms (abdominal pain centered on the right side just under the ribcage, tenderness in the right upper quadrant) are suggestive of a possible gallbladder issue, such as cholecystitis or biliary colic. A HIDA scan is specifically used to evaluate the gallbladder and biliary system. A: Abdominal radiographs would not provide detailed information about the gallbladder or biliary system, and are not the best choice in this scenario. B: A CT scan of the abdomen with contrast can be helpful in some situations, but it may not provide the specific information needed to evaluate the gallbladder and biliary system. C: Right upper quadrant ultrasound is a good initial imaging study for evaluating gallbladder disease, but a HIDA scan is more specific for functional assessment of