Correct Answer: B

Rationale: Binocularity, the ability to fixate on one visual field with both eyes simultaneously, is typically achieved by the age of 3 to 4 months. Achieving binocularity at 1 month is too early for most infants as their visual system is still developing. Similarly, 6 to 8 months and 12 months are beyond the normal age range for achieving binocularity, and delayed achievement could indicate potential issues like strabismus, which may lead to visual impairment if not addressed.

Correct Answer: A

Rationale: Preschoolers may engage in magical thinking and believe inanimate objects are alive, so the nurse should explain the equipment in a way that reduces fear.

Correct Answer: A

Rationale: The history section of the health record includes details about pregnancy, labor, and delivery, as these factors can have significant implications for the child's health.

Correct Answer: C

Rationale: The correct answer is C. Fetal hemoglobin (HbF) is present in high levels during early infancy, inhibiting sickling unlike adult hemoglobin (HbS). As the levels of HbF decrease and HbS increases, the risk of sickling and crises becomes more pronounced, typically after 6 months of age. Choice A is incorrect because it assumes the crisis went unnoticed, which is not supported by medical knowledge. Choice B is incorrect as it questions the child's diagnosis rather than explaining the phenomenon of delayed crises. Choice D is incorrect as it does not provide the parents with the necessary information regarding their query.

Correct Answer: A

Rationale: Poorly managed pain after abdominal surgery can lead to complications like atelectasis due to shallow breathing, which may occur if the child avoids deep breaths because of pain.