Correct Answer: A

Rationale: The correct answer is A: 'Mental retardation occurs if PKU is untreated.' Phenylketonuria (PKU) is a metabolic disorder that, if left untreated with dietary management, can lead to severe mental retardation due to the accumulation of phenylalanine. It is crucial for parents to understand the potential consequences of untreated PKU to emphasize the importance of early and consistent treatment. Choice B is incorrect because testing for PKU is typically done through newborn screening shortly after birth, not immediately. Choice C is incorrect as treatment for PKU primarily involves strict dietary management that restricts phenylalanine intake, not lifelong medications. Choice D is incorrect as PKU is inherited in an autosomal recessive pattern, meaning that both parents must pass on a mutated gene for the disorder to manifest.

Correct Answer: C

Rationale: Asking about the gestational age is crucial in determining the stage of labor and assessing potential complications. This information helps in understanding the progress of labor and making appropriate decisions regarding the management of the delivery process. Choices A, B, and D are not as pertinent at this point in providing immediate care or assessing the situation compared to knowing the gestational age.

Correct Answer: A

Rationale: Administering a bronchodilator is the priority intervention for a child experiencing an acute asthma exacerbation. Bronchodilators help to dilate the airways, making breathing easier and relieving acute symptoms of asthma. Antihistamines are not the first-line treatment for asthma exacerbations; they are more commonly used for allergic reactions. Corticosteroids are beneficial in reducing inflammation in asthma but are usually administered after bronchodilators to provide long-term control. Oxygen therapy may be necessary in severe cases of asthma exacerbation, but bronchodilators take precedence in improving airway patency and respiratory distress.

Correct Answer: B

Rationale: Metatarsus adductus is a condition where the front part of the foot is turned inward. It is often caused by the baby's position in the womb, leading to pressure on the foot during fetal development. Choice A is incorrect as metatarsus adductus is not primarily caused by a genetic defect in the bones. Choice C is incorrect as the cause of metatarsus adductus is known to be related to intrauterine positioning. Choice D is incorrect as metatarsus adductus specifically pertains to the foot and not the hip.

Correct Answer: B

Rationale: Vomiting and poor appetite can be symptoms of neuroblastoma, a malignancy that affects the adrenal glands and sympathetic nervous system. A maculopapular rash on the palms (Choice A) is not typically associated with neuroblastoma. Irritability and poor weight gain (Choice C) may be non-specific findings and do not specifically point towards neuroblastoma. Auscultation findings of wheezing with diminished lung sounds (Choice D) are more indicative of respiratory conditions rather than neuroblastoma.