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: D

Rationale: The correct first step in decontamination is to remove the patient's clothing and jewelry to prevent further exposure and then rinse the patient with water. This helps to eliminate any contaminants on the patient's body. Choice A is incorrect because applying a chemical decontamination foam should come after removing clothing. Choice B is incorrect as washing and rinsing the patient should follow the removal of clothing. Choice C is incorrect as personal protective equipment should be worn by the individual performing the decontamination, not applied to the patient.

Correct Answer: D

Rationale: During endotracheal suctioning, the nurse should apply suctioning while withdrawing and gently rotating the catheter 360 degrees for a short period of 0-5 seconds. This brief duration helps minimize the risk of hypoxia and trauma to the airway. Choices A, B, and C suggest longer time periods for suctioning, which can increase the risk of complications such as hypoxia, mucosal damage, and the removal of excess amounts of airway secretions.

Correct Answer: A

Rationale: The correct answer is 'A: case study.' A case study involves an in-depth examination of a single individual, group, or event. In this scenario, focusing on one boy aligns with the definition of a case study. The other options are not applicable: B) A longitudinal study involves following subjects over a period of time, C) A cross-sectional study examines a population at a single point in time, and D) An evaluative study assesses the effectiveness of a program or intervention, which is not the focus of the given scenario.

Correct Answer: B

Rationale: The correct answer is B because when assessing Richard for chest percussion or chest vibration and postural drainage, Mario would focus on various aspects such as the amount of food and fluid taken before treatment to prevent complications during the procedure, teaching the client's relatives to perform the procedure correctly, and following the doctor's orders regarding position restrictions and the client's tolerance for lying flat. Respiratory rate, breath sounds, and location of congestion would be assessed during the procedure itself, not as part of the pre-assessment.