Correct Answer: B

Rationale: In an extreme situation where no other resident or intern is available, if a nurse receives telephone orders, the order has to be correctly written and signed by the physician within 36 hours. This time frame ensures timely documentation and validation of the orders. Choice A (24 hours) is too short a period for busy physicians to fulfill the task. Choice C (48 hours) is too long and delays the incorporation of physician orders into the patient's care plan. Choice D (12 hours) may not provide enough time for the physician to review and sign the order, especially in situations where immediate attention is not required.

Correct Answer: D

Rationale: In Pure Experimental research, subjects in the experimental group are typically selected randomly to minimize bias and ensure that the results are attributable to the intervention being studied. Therefore, the statement 'There is a careful selection of subjects in the experimental group' is not true. This careful selection would introduce bias and compromise the validity of the experimental results. Choices A, B, and C are true for Pure Experimental research as it involves both a control group, an experimental group, and randomization of subject selection in the control group to ensure comparability.

Correct Answer: B

Rationale: The purpose of the cuff in a Tracheostomy tube is to separate the trachea from the esophagus. The cuff helps prevent aspiration by creating a seal that separates the trachea from the esophagus, reducing the risk of food or fluids entering the lungs. Choices A, C, and D are incorrect because the cuff's primary function in a Tracheostomy tube is to prevent aspiration rather than separating the upper and lower airway, larynx from the nasopharynx, or securing the placement of the tube.

Correct Answer: A

Rationale: During the Emergent phase of burns, the most fatal electrolyte imbalance is Hypokalemia. This is due to the shift of potassium from the intracellular space to the extracellular space, leading to low potassium levels in the blood. Choices B, C, and D are incorrect because Hyperkalemia, Hypernatremia, and Hyponatremia are not typically associated with the Emergent phase of burns and do not pose the same level of risk as Hypokalemia in this context.

Correct Answer: A

Rationale: Primary Nursing involves assigning a dedicated nurse to lead a team of registered nurses in the care of a patient from admission to discharge. This approach ensures continuity and personalized care. Choices B and C are incorrect as they do not accurately describe Primary Nursing. Choice D is incorrect as it refers to a different care delivery model.