Correct Answer: C

Rationale: The correct answer is C: Chronic sinusitis. Untreated asthma can lead to chronic sinusitis in children due to prolonged inflammation and infection of the respiratory tract. Choices A, B, and D are incorrect. Delayed puberty and growth retardation are not common complications of untreated asthma in children. Frequent headaches may be associated with asthma exacerbations but are not typical long-term complications.

Correct Answer: D

Rationale: The correct answer is D. Controls in an experiment ensure that the subjects are similar in all respects except for the treatment being tested. This allows for a fair comparison between the treatment group and the control group. Choice A is incorrect because the size of the groups is not the primary benefit of using controls. Choice B is incorrect as blinding, not controls, refers to subjects not knowing about the experiment. Choice C is incorrect as it pertains more to randomization than the use of controls.

Correct Answer: C

Rationale: Kilojoules are the standard units of energy used by most scientists and nutritionists worldwide. Newtons are units of force, liters are units of volume, and kilocalories are more commonly used in the United States but not as widely adopted internationally for energy measurements. Therefore, the correct answer is 'kilojoules.'

Correct Answer: A

Rationale: Monitoring for signs of infection is crucial in managing a central venous catheter to prevent complications. This involves observing for redness, swelling, warmth, or drainage at the catheter site, as these can indicate an infection. Restricting physical activity unnecessarily (choice B) can hinder the child's recovery and quality of life. Administering routine antibiotics (choice C) without a confirmed infection can lead to antibiotic resistance and unnecessary side effects. Increasing fluid intake only (choice D) is not the primary intervention for managing a central venous catheter.

Correct Answer: A

Rationale: When managing a child with an allergy to multiple food items, the most appropriate approach is to avoid all identified allergens. This is crucial to prevent allergic reactions and ensure the child's safety. Choice B, increasing dietary exposure to allergens, is incorrect as it can lead to severe allergic reactions. Choice C, administering daily antihistamines, may help manage symptoms but does not address the root cause, which is avoiding allergens. Choice D, restricting all food intake, is not a viable option as it can lead to malnutrition and other health issues.