Correct Answer: B

Rationale: A family history of colon polyps and/or colon cancer is a significant risk factor for developing colon cancer. Individuals with a family history are more likely to develop colon cancer due to genetic predisposition. While other factors like irritable bowel syndrome, cirrhosis of the liver, and history of colon surgery may contribute to an increased risk of colon cancer, having a family history of colon polyps is the highest risk factor. Irritable bowel syndrome does not directly increase the risk of colon cancer. Cirrhosis of the liver is associated with liver cancer rather than colon cancer. A history of colon surgery may reduce the risk of colon cancer in some cases by removing precancerous polyps.

Correct Answer: C

Rationale: When the nurse notes scabbing at the edges and a black collection of blood, it indicates the presence of debris that needs to be addressed. Leaving the scabbed area alone and applying extra ointment may not address the underlying issue and could lead to complications. Notifying the physician is important in some cases, but immediate action is required to prevent infection in this situation. Gently removing the debris and re-dressing the wound is the correct course of action to promote healing and prevent complications.

Correct Answer: D

Rationale: Cyanocobalamin is a B12 medication used for pernicious anemia. A reticulocyte count of 1% indicates the desired effect of the medication, as reticulocytes are immature red blood cells that increase in response to B12 therapy, improving anemia. Neutrophils, basophils, and monocytes are white blood cells and are not directly influenced by B12 injections, making them incorrect choices.

Correct Answer: A

Rationale: The correct answer is 'Remove air from the pleural space.' When a client has two chest tubes in place post-thoracotomy, the upper chest tube is typically positioned to remove air from the pleural space. Air rises, so placing the tube at the top allows for efficient removal of air that has accumulated in the pleural cavity. Choice B, creating access for irrigating the chest cavity, is incorrect as chest tubes are not primarily used for irrigation. Choice C, evacuating secretions from the bronchioles and alveoli, is incorrect as chest tubes are not designed for this purpose. Choice D, draining blood and fluid from the pleural space, is also incorrect as the upper chest tube in this scenario is specifically for removing air, not blood or fluid.

Correct Answer: A

Rationale: The most common cause of acute renal failure is shock. In cases of shock, such as hypovolemic shock where there is low blood volume, the kidneys receive inadequate blood flow leading to acute renal failure. This can result in the kidneys starting to die within 20 minutes of low pressure. While nephrotoxic drugs can also cause acute renal failure, shock is more commonly associated with this condition. An enlarged prostate can lead to urinary retention but is not the most common cause of acute renal failure. Diabetes, on the other hand, can cause chronic kidney disease over time but is not typically the primary cause of acute renal failure.