Correct Answer: A

Rationale: The correct answer is A because successful treatment of diabetes insipidus aims to reduce excessive urine output and dehydration. A fluid intake of less than 2,500mL in 24 hours indicates proper control of fluid balance. Choice B is incorrect because urine output of more than 200mL/hour suggests ongoing excessive fluid loss, which is not indicative of successful treatment. Choice C is incorrect as a blood pressure of 90/50mmHg is low and may indicate hypotension, which is not a specific indicator of successful diabetes insipidus treatment. Choice D is incorrect because a pulse rate of 126 beats/min is not a direct marker of diabetes insipidus treatment success. In summary, the correct indicator of successful treatment of diabetes insipidus is a reduction in fluid intake, option A, as it signifies improved fluid balance and hydration status.

Correct Answer: A

Rationale: The correct answer is A: Age-related changes. Older clients are more susceptible to immune system disorders due to age-related changes such as a weakened immune response, increased inflammation, and decreased production of immune cells. Providing special care is important to address these specific vulnerabilities. Incorrect choices: B: Use of multiple drugs (Polypharmacy) - While polypharmacy can impact the immune system, it is not the primary factor for providing special care to older clients with immune system disorders. C: Poor diet - While diet plays a role in overall health, it is not the main factor necessitating special care for older clients with immune system disorders. D: Reduced activity levels - Although physical activity is important for overall health, reduced activity levels are not the primary reason for providing special care to older clients with immune system disorders.

Correct Answer: A

Rationale: Correct Answer: A: Respiratory acidosis Rationale: 1. Respiratory acidosis is caused by inadequate ventilation leading to increased PCO₂ and decreased pH. 2. Low pH indicates acidosis, and high PCO₂ indicates respiratory component. 3. Metabolic acidosis (B) results from non-respiratory causes. 4. Respiratory alkalosis (C) is characterized by high pH and low PCO₂. 5. Metabolic alkalosis (D) is caused by non-respiratory factors with high pH.

Correct Answer: C

Rationale: Objective data are measurable and observable facts. Respirations (C) of 16 per minute is objective data as it is a quantifiable measurement that can be counted and recorded. It is not influenced by personal interpretation or bias. Choices A, B, and D are subjective data as they rely on the patient's feelings, perceptions, or symptoms, which can vary and are open to interpretation. Therefore, choice C is the correct answer as it represents concrete, verifiable information that can be used in the patient's assessment and care planning.

Correct Answer: D

Rationale: The correct answer is D: Sigmoidoscopy. Sigmoidoscopy is a direct visualization procedure that allows for examination of the lower part of the colon and rectum, where colorectal cancer commonly occurs. This procedure can help identify any abnormal growths or polyps that may indicate cancer. Stool hematest (A) detects blood in stool but does not confirm colorectal cancer. Abdominal CT (B) provides imaging of the abdomen but may not definitively diagnose colorectal cancer. CEA scan (C) measures a tumor marker associated with colorectal cancer but is not a definitive diagnostic test. Thus, sigmoidoscopy is the most appropriate diagnostic study for confirming colorectal cancer.