Correct Answer: A

Rationale: The correct answer is A, Excitability. Excitability is the ability of cardiac cells to respond to a stimulus by initiating a cardiac impulse. Choice B, Contractility, refers to the ability of cardiac muscle to shorten forcibly. Choice C, Rhythmicity, refers to the cardiac muscle's ability to contract rhythmically. Choice D, Conductivity, refers to the ability of the heart's cells to conduct electrical impulses.

Correct Answer: B

Rationale: The correct answer is B. A heart rate of 58 bpm is considered low, and beta blockers can further decrease the heart rate. Therefore, the nurse's priority action should be to hold the beta blocker and notify the healthcare provider for further assessment. Choice A is incorrect because administering the beta blocker without considering the low heart rate can worsen the condition. Choice C is incorrect as increasing the dose of the beta blocker can lead to further slowing of the heart rate, which is not safe in this situation. Choice D is not the priority action; holding the medication and seeking guidance from the healthcare provider is more crucial.

Correct Answer: A

Rationale: The correct answer is A: Arrhythmia. Arrhythmia is a broad term that refers to any irregularity in the heart's rhythm, which can manifest as a heartbeat that is too fast (tachycardia), too slow (bradycardia), or irregular. Choice B, Bradycardia, specifically denotes a slow heart rate, while choice C, Tachycardia, refers to a fast heart rate. Choice D, Conductivity, is not the correct term to describe an abnormal heartbeat characterized by speed irregularities.

Correct Answer: A

Rationale: The correct answer is A, Chronic bronchitis. Chronic bronchitis involves long-term inflammation of the bronchi, leading to excessive mucus production, frequent coughing, and breathing difficulties. Asthma (B) is characterized by reversible airway obstruction and bronchospasms. Pneumonia (C) is an infection of the lungs caused by bacteria, viruses, or fungi. COPD (D) is a term used to describe chronic lung diseases that cause airflow blockage and breathing-related problems.

Correct Answer: A

Rationale: The correct answer is Aortic stenosis. In aortic stenosis, the aortic valve becomes narrowed, which obstructs the blood flow from the heart to the rest of the body. This condition can lead to symptoms like chest pain, shortness of breath, and fainting. Mitral stenosis (choice B) involves narrowing of the mitral valve, not the aortic valve. Tricuspid regurgitation (choice C) is a condition where the tricuspid valve leaks, causing blood to flow backward in the heart. Pulmonary hypertension (choice D) is high blood pressure in the arteries of the lungs.