Correct Answer: B

Rationale: Hypokalemia, a condition characterized by low levels of potassium in the blood, is reflected in an ECG by a widening QRS Complex and a U wave. This is because potassium plays a key role in the electrical activity of the heart, and its deficiency can lead to abnormalities in the heart's rhythm as represented by these specific changes on the ECG. Choice A is incorrect as tall T waves and pathologic Q waves are more commonly associated with hyperkalemia or myocardial infarction, respectively, rather than hypokalemia. Choices C and D are also incorrect as they do not accurately reflect the ECG changes caused by hypokalemia.

Correct Answer: D

Rationale: The correct answer is D: Potential risk of foodborne illness. Patients undergoing chemotherapy have compromised immune systems, making them more susceptible to foodborne illnesses. Chemotherapy can reduce the count of white blood cells, which impairs the body's ability to fight off infections from bacteria or other pathogens that might be present in food. Therefore, the prevention of foodborne illnesses is a critical concern for these patients. Choices A, B, and C, while they represent valid concerns for food safety in general, are not the primary concern for patients undergoing chemotherapy. These patients are at a heightened risk of experiencing severe complications from foodborne illnesses, making it a more significant concern than potential food allergies, food-drug interactions, or pesticide residues.

Correct Answer: C

Rationale: The QRS Complex in an ECG reading represents ventricular depolarization, which is the process of the heart's ventricles preparing to contract by changing the electrical charge in the cell, hence choice 'C' is the correct answer. Choice 'A' is incorrect because atrial depolarization is represented by the P wave in an ECG reading, not the QRS Complex. Choice 'B' is incorrect as ventricular repolarization is depicted by the T wave, not the QRS Complex. Finally, choice 'D' is also incorrect because the QRS Complex is not the end of ventricular depolarization, but the process itself.

Correct Answer: D

Rationale: When measuring blood pressure, the cuff should be inflated to 30 mmHg above the estimated systolic blood pressure based on palpation of the radial or brachial artery. This ensures an accurate blood pressure measurement. Choices A, B, and C are incorrect. Deflating the cuff fully before starting a second reading (Choice A) does not directly relate to the position of the cuff during a reading. Deflating the cuff quickly after inflating to 180 mmHg (Choice B) is not recommended because it can potentially lead to inaccurate readings. While ensuring the cuff is large enough to wrap around the upper arm positioned 1 cm above the brachial artery is important (Choice C), this alone does not guarantee an accurate blood pressure reading. The correct inflation based on palpation is the key element for accuracy, which is why Choice D is correct.

Correct Answer: C

Rationale: The correct answer is C. While it is true that Mrs. Guevarra is delegating tasks to the nurse-aide, she does not necessarily have to directly supervise or evaluate the aide. She still retains the overall accountability for the care of the client, but direct supervision of the aide is not a requirement for delegation. Choice A is incorrect because the primary purpose of delegation is not instruction. Choice B is also incorrect because although Mrs. Guevarra is delegating tasks, she still retains accountability for those tasks. Finally, choice D is incorrect because the ability to perform the task being delegated is not a requirement for the delegator; the delegatee should have the necessary skills and knowledge to perform the delegated tasks.