Correct Answer: A

Rationale: The correct answer is A. The use of placebos without the patient's consent is unethical and goes against the principles of beneficence and autonomy. Choice B is incorrect because using placebos does not provide reliable information about the presence or severity of the pain; it only indicates the response to the placebo itself. Choice C is wrong as the absence of a response to a placebo does not definitively mean that the child's pain has an organic basis; there could be various reasons for the lack of response. Choice D is also incorrect as individuals may have a positive response to a placebo even if their pain has a significant organic cause. Therefore, the most appropriate response is A, emphasizing the ethical concerns surrounding the use of placebos without informed consent.

Correct Answer: C

Rationale: Implanted ports like the Port-a-Cath are fully implanted under the skin, allowing the child to maintain regular physical activities, including swimming, without the risk of dislodging the catheter. Piercing the skin is still required for access, and self-administration is more complex.

Correct Answer: D

Rationale: Dry mucous membranes and an ill appearance are good indicators of dehydration in infants, often correlating with a fluid deficit of at least 5%. Sunken fontanels and poor skin turgor are also indicative but were not options here.

Correct Answer: C

Rationale: The correct answer is C. Introducing iron-fortified cereal between 4 to 6 months of age is a recommended practice to prevent iron deficiency anemia in infants. Iron-fortified infant cereals are a good source of iron for infants. Choices A and B are incorrect because adding green leafy vegetables to low-iron formula and discontinuing vitamin C supplements do not directly address the prevention of iron deficiency anemia. Choice D is incorrect because cow's milk should be avoided before 12 months of age as it is low in iron and can lead to intestinal blood loss, increasing the risk of iron deficiency anemia.

Correct Answer: C

Rationale: The correct response is to let the parents know they are allowed to stay with the child. Allowing parents to stay with the child can help reduce the child's anxiety and provide comfort. Choice A is incorrect as the parents should be encouraged to stay with their child. Choice B is not the immediate response the nurse should provide. Choice D is inappropriate as it does not address the benefits and importance of parental presence for the child's well-being during hospitalization.